451
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McCooey SH, McCabe T, Connon SJ. Stereoselective Synthesis of Highly Functionalized Nitrocyclopropanes via Organocatalyic Conjugate Addition to Nitroalkenes. J Org Chem 2006; 71:7494-7. [PMID: 16958552 DOI: 10.1021/jo0613838] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A convenient and novel one-pot organocatalytic methodology for the stereoselective synthesis of highly functionalized nitrocyclopropanes is reported. The addition of dimethyl chloromalonate to a variety of nitroolefins catalyzed by tertiary amines leads to a Michael adduct which cyclizes to form the cyclopropane in the presence of DBU under carefully controlled reaction conditions with outstanding diastereoselectivity.
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Affiliation(s)
- Séamus H McCooey
- Centre for Synthesis and Chemical Biology and School of Chemistry, University of Dublin, Trinity College, Dublin 2, Ireland
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452
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Bruneau C. Electrophilic activation and cycloisomerization of enynes: a new route to functional cyclopropanes. Angew Chem Int Ed Engl 2006; 44:2328-34. [PMID: 15761893 DOI: 10.1002/anie.200462568] [Citation(s) in RCA: 332] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Transformations of enynes in the presence of transition-metal catalysts have played an important role in the preparation of a variety of cyclic compounds. Recent developments in the activation of triple carbon-carbon bonds by electrophilic metal centers have provided a new entry to the selective synthesis of cyclopropane derivatives from enynes. The mechanisms of these reactions involve catalytic species with both ionic and cyclopropylcarbenoid character. This type of activation will undoubtedly be further developed for application to other unsaturated hydrocarbons and inspire new catalytic cascade reaction sequences. This Minireview discusses the recent developments in electrophilic activation of enynes and shows that simple catalysts such as [Ru(3)(CO)(12)], PtCl(2), and cationic gold complexes are efficient precursors to promote the formation of functional polyclic compounds.
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Affiliation(s)
- Christian Bruneau
- Institut de Chimie, UMR 6509: CNRS-Université de Rennes 1, Organométalliques et Catalyse, Rennes Cedex, France.
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453
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Deng XM, Cai P, Ye S, Sun XL, Liao WW, Li K, Tang Y, Wu YD, Dai LX. Enantioselective Synthesis of Vinylcyclopropanes and Vinylepoxides Mediated by Camphor-Derived Sulfur Ylides: Rationale of Enantioselectivity, Scope, and Limitation. J Am Chem Soc 2006; 128:9730-40. [PMID: 16866528 DOI: 10.1021/ja056751o] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
By a sidearm approach, camphor-derived sulfur ylides 1 were designed and synthesized for the cyclopropanation of electron-deficient alkenes and epoxidation of aldehydes. Under the optimal conditions, the exo-type sulfonium salts 4a and 4b reacted with beta-aryl-alpha,beta-unsaturated esters, amides, ketones, and nitriles to give 1,3-disubstituted-2-vinylcyclopropanes with high diastereoselectivities and enantioselectivities. When the endo-type sulfonium salts 5a and 5b were used, the diastereoselectivities were not changed, whereas the absolute configurations of the products became the opposite to those of the reactions of 4a and 4b. An ylide cyclopropanation of chalcone derivatives with phenylvinyl bromide in the presence of catalytic amount of chiral sulfonium salts 4b and 5b has been developed. The sidearmed hydroxyl group was found to play a key role in the control of enantioselectivity and diastereoselectivity. The origins of the high diastereoselectivity and enantioselectivity were also studied by density functional theory calculations, which reveal the importance of the hydrogen-bonding between the sidearmed hydroxyl group and the substrate in determining the diastereoselectivity and enantioselectivity. The ylides 1 were also successfully applied for the epoxidation of aromatic aldehydes.
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Affiliation(s)
- Xian-Ming Deng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, China
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454
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McAllister GD, Oswald MF, Paxton RJ, Raw SA, Taylor RJ. The direct preparation of functionalised cyclopropanes from allylic alcohols or α-hydroxyketones using tandem oxidation processes. Tetrahedron 2006. [DOI: 10.1016/j.tet.2005.12.078] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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455
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Diev VV, Kostikov RR, Gleiter R, Molchanov AP. Cyclopropenes in the 1,3-Dipolar Cycloaddition with Carbonyl Ylides: Experimental and Theoretical Evidence for the Enhancement of σ-Withdrawal in 3-Substituted-Cyclopropenes. J Org Chem 2006; 71:4066-77. [PMID: 16709045 DOI: 10.1021/jo0600656] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The carbonyl ylide dipoles generated by the dirhodium tetra-acetate-catalyzed decomposition of diazocarbonyl precursors 1, 5, and 8 cycloadd to 3-substituted 1,2-diphenylcyclopropenes 3a-e and 3,3-disubstituted cyclopropenes 13, 14, 19, and 20 to give polycyclic compounds with 8-oxatricyclo[3.2.1.0(2,4)]octane and 9-oxatricyclo[3.3.1.0(2,4)]nonane frameworks. Generally, reactions proceed stereoselectively to give adducts of exo stereochemistry with the approach of the carbonyl ylide dipoles from the less-hindered face of cyclopropenes. The electronic properties of the substituent at the C3 position of cyclopropenes play an important role in governing the reactivity of cyclopropenes: when the C3 position is substituted by electron-acceptors such as the methoxycarbonyl or cyano groups, the yields of adducts are decreased significantly or no adducts can be detected at all. Relative reactivities of cyclopropenes were quantified by competition experiments to give the best correlation with sigmaF-Taft constants. Both measured photoelectron spectra and ground-state calculations of a series of 1,2-diphenylcyclopropenes indicate considerable lowering of cyclopropene pi-HOMO energies by substitution with an acceptor group. Such changes in electronic structures of cyclopropenes may cause the inversion of frontier molecular orbital (FMO) interactions from HOMO(cyclopropene)-LUMO(ylide) to LUMO(cyclopropene)-HOMO(ylide) type. In terms of philicity, nucleophilic properties of acceptor-substituted cyclopropenes are diminished to such an extent that these species are no longer good nucleophiles in the reaction with carbonyl ylides, and neither are they good electrophiles, being unreactive. This was shown by the B3LYP calculations of addends.
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Affiliation(s)
- Vyacheslav V Diev
- Department of Chemistry, Saint Petersburg State University, 198504 Universitetsky pr. 26, Saint Petersburg, Russian Federation
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456
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Escudero C, Pérez-Prieto J, Stiriba SE. Part II. Chiral dirhodium (II) catalysts with ortho-metalated arylphosphane ligands in the enantioselective intramolecular cyclopropanation of a racemic α-diazo ketone. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2005.06.057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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457
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Abstract
Computed [B3LYP/6-31+G(d,p) and MP2/6-31+G(d,p)] structures and binding energies for complexes of nonclassical cations (carbonium ions) with ammonia, in the gas phase and several solvents, are described. Overall, nonclassical cations are found to be competent C-H hydrogen bond donors. The potential relevance of the C-H...N interactions holding the carbocation.amine complexes together for enzyme-catalyzed terpenoid synthesis is discussed.
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Affiliation(s)
- Mihaela D Bojin
- Department of Chemistry, University of California, Davis, One Shields Avenue, 95616, USA
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458
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Miura T, Sasaki T, Harumashi T, Murakami M. Vinylcyclopropanation of Olefins via 3-Methoxy-1-propenylrhodium(I). J Am Chem Soc 2006; 128:2516-7. [PMID: 16492018 DOI: 10.1021/ja0575326] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
New cyclization reactions forming vinylcyclopropanes were developed wherein an alkenylrhodium(I) possessing a methoxy group at the allylic position as a potential leaving group acts as an allylic carbene equivalent. By this protocol, a vinylcyclopropane was installed in a complex cyclic structure in a single operation via successive multiple carbon-carbon bond formations.
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Affiliation(s)
- Tomoya Miura
- Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Japan
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459
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Yin J, Chisholm JD. Palladium-catalyzed addition of alkynes to cyclopropenes. Chem Commun (Camb) 2006:632-4. [PMID: 16446833 DOI: 10.1039/b516021a] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The palladium catalyzed coupling of alkynes and cyclopropenes provides a powerful method for the synthesis of alkynylcyclopropanes, proceeding under mild conditions in the presence of many functional groups (such as esters, carboxylic acids, aldehydes, and alcohols).
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Affiliation(s)
- Jiandong Yin
- Department of Chemistry, 1-014 Center for Science and Technology, Syracuse University, Syracuse, NY 13244, USA
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460
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Marion N, de Frémont P, Lemière G, Stevens ED, Fensterbank L, Malacria M, Nolan SP. AuI-catalyzed cycloisomerization of 1,5-enynes bearing a propargylic acetate: formation of unexpected bicyclo[3.1.0]hexene. Chem Commun (Camb) 2006:2048-50. [PMID: 16767271 DOI: 10.1039/b602839j] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of N-heterocyclic carbene (NHC) as a ligand in the gold(I)-catalyzed cycloisomerization of enyne results in the assembly of a new carbocyclic product.
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Affiliation(s)
- Nicolas Marion
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA
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461
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Matsuda SPT, Wilson WK, Xiong Q. Mechanistic insights into triterpene synthesis from quantum mechanical calculations. Detection of systematic errors in B3LYP cyclization energies. Org Biomol Chem 2006; 4:530-43. [PMID: 16446812 DOI: 10.1039/b513599k] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Most quantum mechanical studies of triterpene synthesis have been done on small models. We calculated mPW1PW91/6-311+G(2d,p)//B3LYP/6-31G* energies for many C30H51O+ intermediates to establish the first comprehensive energy profiles for the cationic cyclization of oxidosqualene to lanosterol, lupeol, and hopen-3beta-ol. Differences among these 3 profiles were attributed to ring strain, steric effects, and proton affinity. Modest activation energy barriers and the ample exothermicity of most annulations indicated that the cationic intermediates rarely need enzymatic stabilization. The course of reaction is guided by hyperconjugation of the carbocationic 2p orbital with parallel C-C and C-H bonds. Hyperconjugation for cations with a horizontal 2p orbital (in the plane of the ABCD ring system) leads to annulation and ring expansion. If the 2p orbital becomes vertical, hyperconjugation fosters 1,2-methyl and hydride shifts. Transition states leading to rings D and E were bridged cyclopropane/carbonium ions, which allow ring expansion/annulation to bypass formation of undesirable anti-Markovnikov cations. Similar bridged species are also involved in many cation rearrangements. Our calculations revealed systematic errors in DFT cyclization energies. A spectacular example was the B3LYP/6-311+G(2d,p)//B3LYP/6-31G* prediction of endothermicity for the strongly exothermic cyclization of squalene to hopene. DFT cyclization energies for the 6-311+G(2d,p) basis set ranged from reasonable accuracy (mPW1PW91, TPSSh with 25% HF exchange) to underestimation (B3LYP, HCTH, TPSS, O3LYP) or overestimation (MP2, MPW1K, PBE1PBE). Despite minor inaccuracies, B3LYP/6-31G* geometries usually gave credible mPW1PW91 single-point energies. Nevertheless, DFT energies should be used cautiously until broadly reliable methods are established.
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Affiliation(s)
- Seiichi P T Matsuda
- Department of Chemistry, Rice University, 6100 Main Street, Houston, TX 77005, USA.
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462
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Abstract
Aklanonic acid, an anthraquinone natural product, is a common advanced intermediate in the biosynthesis of several antitumor polyketide antibiotics, including doxorubicin and aclacinomycin A. Intensive semisynthetic and biosynthetic efforts have been directed toward developing improved analogues of these clinically important compounds. The primer unit of such polyfunctional aromatic polyketides is an attractive site for introducing novel chemical functionality, and attempts have been made to modify the primer unit by precursor-directed biosynthesis or protein engineering of the polyketide synthase (PKS). We have previously demonstrated the feasibility of engineering bimodular aromatic PKSs capable of synthesizing unnatural hexaketides and octaketides. In this report, we extend this ability by preparing analogues of aklanonic acid, a decaketide, and its methyl ester. For example, by recombining the R1128 initiation module with the dodecaketide-specific pradimicin PKS, the isobutyryl-primed analogue of aklanonic acid (YT296b, 10) and its methyl ester (YT299b, 12) were prepared. In contrast, elongation modules from dodecaketide-specific spore pigment PKSs were unable to interact with the R1128 initiation module. Thus, in addition to revealing a practical route to new anthracycline antibiotics, we also observed a fundamental incompatibility between antibiotic and spore pigment biosynthesis in the actinomycetes bacteria.
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Affiliation(s)
| | - Chaitan Khosla
- Department of Chemistry
- Chemical Engineering, and
- Biochemistry, Stanford University, Stanford, California 94305
- *To whom correspondence should be addressed: Chaitan Khosla, Department of Chemistry, Chemical Engineering, and Biochemistry, Stanford University, Stanford, CA 94305. E-mail:
| | - Yi Tang
- Department of Chemical Engineering, University of California at Los Angeles, Los Angeles, CA, 90095
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463
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464
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Kim HY, Lurain AE, García-García P, Carroll PJ, Walsh PJ. Highly Enantio- and Diastereoselective Tandem Generation of Cyclopropyl Alcohols with up to Four Contiguous Stereocenters. J Am Chem Soc 2005; 127:13138-9. [PMID: 16173729 DOI: 10.1021/ja0539239] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three highly enantio- and diastereoselective one-pot procedures for the synthesis of cyclopropyl and iodocyclopropyl alcohols with up to four contiguous stereocenters are reported. Route 1 involves asymmetric addition of an alkylzinc reagent to an enal followed by diastereoselective cyclopropanation. Route 2 parallels route 1, except that iodoform is used to generate the zinc carbenoid, and the products are iodocyclopropyl alcohols. Route 3 entails asymmetric vinylation of an aldehyde with divinylzinc reagents and subsequent diastereoselective cyclopropanation.
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Affiliation(s)
- Hun Young Kim
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
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465
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Fournier JF, Mathieu S, Charette AB. Diastereoselective Zinco-Cyclopropanation of Chiral Allylic Alcohols withgem-Dizinc Carbenoids. J Am Chem Soc 2005; 127:13140-1. [PMID: 16173730 DOI: 10.1021/ja054328+] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The highly diastereoselective zinco-cyclopropanation of chiral allylic alcohols using gem-dizinc carbenoids is described. The reaction produces three contiguous stereogenic centers, and the resulting chiral cyclopropylzinc derivatives can be trapped with electrophiles with retention of configuration. Simple functional group manipulations lead to the efficient synthesis of orthogonally protected 1,2,3-substituted cyclopropane derivatives.
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466
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Schelper M, Buisine O, Kozhushkov S, Aubert C, de Meijere A, Malacria M. Cobalt(I)-Mediated Intramolecular [2+2+2] Cocyclizations of (Methylenecyclopropyl)diynes as an Easy Access to Cyclopropanated Oligocycles. European J Org Chem 2005. [DOI: 10.1002/ejoc.200500111] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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467
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Kordes M, Brands M, Es-Sayed M, de Meijere A. Preparation of Cyclopropane Analogues of the Natural AntibioticTAN 1057 A/B. European J Org Chem 2005. [DOI: 10.1002/ejoc.200500177] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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468
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Brackmann F, Es-Sayed M, de Meijere A. Synthesis of Spirocyclopropanated Analogues of Iprodione. European J Org Chem 2005. [DOI: 10.1002/ejoc.200400600] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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469
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Yamashita M, Inaba T, Nagahama M, Shimizu T, Kosaka S, Kawasaki I, Ohta S. Novel stereoconvergent transformation of 1,2a-disubstituted 1,2,2a,8b-tetrahydro-3H-benzo[b]cyclobuta[d]pyran-3-ones to 1,3-disubstituted 1,2,4a,9b-tetrahydrodibenzofuran-4-ols and its application to the second-generation synthesis of (+/-)-linderol A. Org Biomol Chem 2005; 3:2296-304. [PMID: 16010364 DOI: 10.1039/b503890a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1,2a-Disubstituted 1,2,2a,8b-tetrahydro-3H-benzo[b]cyclobuta[d]pyran-3-ones bearing an electron-withdrawing group at the 2a-position were treated with two equivalents of dimethylsulfoxonium methylide to give r-1,t-4a,t-9b-1,3-disubstituted 1,2,4a,9b-tetrahydrodibenzofuran-4-ols stereoconvergently regardless of the stereochemistry of the 1-position on the benzocyclobutapyran ring. This methodology was applied to the second-generation synthesis of (+/-)-linderol A, a melanin biosynthesis inhibitory natural product.
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Affiliation(s)
- Masayuki Yamashita
- Department of Functional Molecular Chemistry, 21st COE Program, Kyoto Pharmaceutical University, Misasagi-Nakauchi 5, Yamashina, Kyoto 607-8414, Japan
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470
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Huang X, Yu L, Chen Z. Tandem Michael–Nucleouphilic Addition of 2‐Cyclopropylidene Propionaldehyde—A Novel Method for the Synthesis of Spirocyclopropane‐Annulated Heterocycles. SYNTHETIC COMMUN 2005. [DOI: 10.1081/scc-200054852] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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471
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Gutta P, Tantillo DJ. Proton Sandwiches: Nonclassical Carbocations with Tetracoordinate Protons. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200461915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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472
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Gutta P, Tantillo DJ. Proton Sandwiches: Nonclassical Carbocations with Tetracoordinate Protons. Angew Chem Int Ed Engl 2005; 44:2719-2723. [PMID: 15822137 DOI: 10.1002/anie.200461915] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Pradeep Gutta
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA, Fax: (+1) 530-752-8995
| | - Dean J Tantillo
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA, Fax: (+1) 530-752-8995
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473
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Bruneau C. Elektrophile Aktivierung und Cycloisomerisierung von Eninen: ein Weg zu funktionalen Cyclopropanen. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200462568] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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474
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Salaün J. π-1,1-Dimethyleneallylmetal and Homologous Complexes: Their Application in Organic Synthesis. Chem Rev 2005; 105:285-312. [PMID: 15720155 DOI: 10.1021/cr040201b] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jacques Salaün
- Laboratoire des Carbocycles (CNRS, UMR 8615), Institut de Chimie Moléculaire et des Matériaux d'Orsay, Bât. 420, Université de Paris-Sud, 91405 Orsay, France.
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475
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Laroche C, Harakat D, Bertus P, Szymoniak J. Studies on the titanium-catalyzed cyclopropanation of nitriles. Org Biomol Chem 2005; 3:3482-7. [PMID: 16172684 DOI: 10.1039/b508367b] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Ti-mediated reaction of Grignard reagents with nitriles was investigated with sub-stoichiometric amounts of titanium isopropoxide. Cyanoesters were converted to spirocyclopropanelactams in good yields using as low as 0.05 eq of Ti(O(i)Pr)4. Under similar conditions, cyanocarbonates led to spirocyclopropane oxazolidinones and/or aminocyclopropylcarbinols. A very short synthesis of the naturally occurring aminocyclopropanecarboxylic acid illustrates the usefulness of this methodology.
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Affiliation(s)
- Christophe Laroche
- UMR 6519--Réactions Sélectives et Applications, CNRS-Université de Reims Champagne-Ardenne, BP 1039, 51687 REIMS Cedex 2, France
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476
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Wessjohann LA, Ruijter E, Garcia-Rivera D, Brandt W. What can a chemist learn from nature?s macrocycles? ? A brief, conceptual view. Mol Divers 2005; 9:171-86. [PMID: 15789564 DOI: 10.1007/s11030-005-1314-x] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Macrocyclic natural products often display remarkable biological activities, and many of these compounds (or their derivatives) are used as drugs. The chemical diversity of these compounds is immense and may provide inspiration for innovative drug design. Therefore, a database of naturally occurring macrocycles was analyzed for ring size, molecular weight distribution, and the frequency of some common substructural motifs. The underlying principles of the chemical diversity are reviewed in terms of biosynthetic origin and nature's strategies for diversity and complexity generation in relation to the structural diversity and similarities found in the macrocycle database. Finally, it is suggested that synthetic chemists should use not only nature's molecules, but also nature's strategies as a source of inspiration. To illustrate this, the biosynthesis of macrocycles by non-ribosomal peptide synthetases and terpene and polyketide cyclases, as well as recent advances of these strategies in an integrated synthesis/biotechnology approach are briefly reviewed.
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Affiliation(s)
- Ludger A Wessjohann
- Leibniz-Institute of Plant Biochemistry, Department of Bioorganic Chemistry, Weinberg 3, D-06120 Halle (Saale), Germany,
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477
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Iwig DF, Grippe AT, McIntyre TA, Booker SJ. Isotope and elemental effects indicate a rate-limiting methyl transfer as the initial step in the reaction catalyzed by Escherichia coli cyclopropane fatty acid synthase. Biochemistry 2004; 43:13510-24. [PMID: 15491158 DOI: 10.1021/bi048692h] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cyclopropane fatty acid (CFA) synthases catalyze the formation of cyclopropane rings on unsaturated fatty acids (UFAs) that are natural components of membrane phospholipids. The methylene carbon of the cyclopropane ring derives from the activated methyl group of S-adenosyl-L-methionine (AdoMet), affording S-adenosyl-L-homocysteine (AdoHcys) and a proton as the remaining products. This reaction is unique among AdoMet-dependent enzymes, because the olefin of the UFA substrate is isolated and unactivated toward nucleophilic or electrophilic addition, raising the question as to the timing and mechanism of proton loss from the activated methyl group of AdoMet. Two distinct reaction schemes have been proposed for this transformation; however, neither was based on detailed in vitro mechanistic analysis of the enzyme. In the preceding paper [Iwig, D. F. and Booker, S. J. (2004) Biochemistry 43, http://dx.doi.org/10.1021/bi048693+], we described the synthesis of two analogues of AdoMet, Se-adenosyl-L-selenomethionine (SeAdoMet) and Te-adenosyl-L-telluromethionine (TeAdoMet), and their intrinsic reactivity toward polar chemistry in which AdoMet is known to be involved. We found that the electrophilicity of AdoMet and its onium congeners followed the series SeAdoMet > AdoMet > TeAdoMet, while the acidity of the carbons adjacent to the relevant heteroatom followed the series AdoMet > SeAdoMet > TeAdoMet. When each of these compounds was used as the methylene donor in the CFA synthase reaction, the kinetic parameters of the reaction, k(cat) and k(cat) K(M)(-1), followed the series SeAdoMet > AdoMet > TeAdoMet, suggesting that the reaction takes place via methyl transfer followed by proton loss, rather than by processes that are initiated by proton abstraction from AdoMet. Use of S-adenosyl-L-[methyl-d(3)]methionine as the methylene donor resulted in an inverse isotope effect of 0.87 +/- 0.083, supporting this conclusion and also indicating that the methyl transfer takes place via a tight s(N)2 transition state.
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Affiliation(s)
- David F Iwig
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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478
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Nishibayashi Y, Yoshikawa M, Inada Y, Hidai M, Uemura S. Ruthenium- and Platinum-Catalyzed Sequential Reactions: Selective Synthesis of Fused Polycyclic Compounds from Propargylic Alcohols and Alkenes. J Am Chem Soc 2004; 126:16066-72. [PMID: 15584741 DOI: 10.1021/ja045532k] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A simple method for the preparation of fused polycyclic compounds by an intramolecular cyclization of propargylic alcohols bearing an alkene moiety at a suitable position has been developed, where the presence of both Ru and Pt catalysts promotes a sequence of catalytic cycles in the same medium. This sequential system can be applied to an intermolecular reaction between a propargylic alcohol and an alkene to obtain the corresponding bicyclo[3,1,0]hex-2-ene derivative. These sequential reactions provide a conceptually new type of cycloaddition system between propargylic alcohols and alkenes.
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Affiliation(s)
- Yoshiaki Nishibayashi
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
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479
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Kulinkovich O. Synthetic Applications of Intermolecular Cyclopropanation of Carboxylic Esters with Dialkoxytitanacyclopropane Reagents. European J Org Chem 2004. [DOI: 10.1002/ejoc.200400234] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Oleg Kulinkovich
- Department of Chemistry, Belorussian State University, Fr. Skariny Av. 4, Minsk 220 050, Belarus, Fax: (internat.) + 7‐375‐(17)226‐4998
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480
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Wang Y, Zhao X, Li Y, Lu L. Stereospecific synthesis of trifluoromethyl-substituted polyfunctionalized cyclopropanes. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.08.064] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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481
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Kerber WD, Koh JH, Gagné MR. Platinum(II)-Catalyzed 1,6-Diene Cycloisomerizations: Turnover in the Absence of β-Hydride Elimination. Org Lett 2004; 6:3013-5. [PMID: 15330671 DOI: 10.1021/ol048780u] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electrophilic pincer-ligated Pt(II)-dications are efficient catalysts for the cycloisomerization of 1,6-dienes, initiated by alkene activation. The tridentate ligands inhibit beta-hydride elimination and thus enable cationic mechanisms that turnover by Pt(II) extrusion. PPP ligands lead to cyclopropane products, while PNP ligands provide cyclohexene products; mechanistic issues are also discussed.
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Affiliation(s)
- William D Kerber
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA
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482
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Slootweg JC, Schakel M, de Kanter FJJ, Ehlers AW, Kozhushkov SI, de Meijere A, Lutz M, Spek AL, Lammertsma K. Branched Phospha[7]triangulanes. J Am Chem Soc 2004; 126:3050-1. [PMID: 15012125 DOI: 10.1021/ja031648p] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A highly strained, thermally stable (up to 150 degrees C) branched phospha[7]triangulane was synthesized from the second-generation bicyclopropylidene and transient phosphinidene [Ph-P=W(CO)5], followed by demetalation in refluxing xylene. Bulkier transient CuCl-alkene-complexed phosphinidene gave 2-phosphabicyclo-[3.2.0]hept-1(5)-ene as an additional product. The "outer sphere" spirocyclopropanes provide a stabilizing factor for both of these novel compounds.
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Affiliation(s)
- J Chris Slootweg
- Department of Chemistry, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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483
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Casey CP, Strotman NA. Stereochemistry of Cyclopropane Formation Involving Group IV Organometallic Complexes. J Am Chem Soc 2004; 126:1699-704. [PMID: 14871100 DOI: 10.1021/ja030436p] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of (Z)-HDC=CHCH(OCH(3))C(6)H(5) (1) with Cp(2)Zr(D)Cl followed by BF(3).OEt(2) gave phenylcyclopropanes 3a and 3b, both having cis deuterium. This stereochemical outcome requires inversion of configuration at the carbon bound to zirconium and is consistent with a "W-shaped" transition state structure for cyclopropane formation. In a Kulinkovich hydroxycyclopropanation, trans-3-deutero-1-methyl-cis-2-phenyl-1-cyclopropanol (5) was formed stereospecifically from Ti(O-i-Pr)(4), ethyl acetate, EtMgBr, and trans-beta-deuterostyrene. This stereochemistry requires retention of configuration at the carbon bound to titanium and is consistent with frontside attack of the carbon-titanium bond on a carbonyl group coordinated to titanium. In a de Meijere cyclopropylamine synthesis, a 3:1 mixture of N,N-dimethyl-N-(trans-3-deutero-trans-2-phenylcyclopropyl)amine (6a) and N,N-dimethyl-N-(cis-3-deutero-cis-2-phenylcyclopropyl)amine (6b) was formed from Ti(O-i-Pr)(4), DMF, Grignard reagents, and trans-beta-deuterostyrene. This stereochemistry requires inversion of configuration at the carbon bound to titanium and is consistent with a W-shaped transition structure for ring closure.
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Affiliation(s)
- Charles P Casey
- Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA.
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484
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Sheshenev AE, Baird MS, Croft AK, Bolesov IG. Generation and stereocontrolled trapping of 3-phenylcyclopropene and its derivatives. MENDELEEV COMMUNICATIONS 2004. [DOI: 10.1070/mc2004v014n06abeh002061] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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485
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Liao WW, Li K, Tang Y. Controllable Diastereoselective Cyclopropanation. Enantioselective Synthesis of Vinylcyclopropanes via Chiral Telluronium Ylides. J Am Chem Soc 2003; 125:13030-1. [PMID: 14570468 DOI: 10.1021/ja036254c] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Novel chiral telluronium salts 1 are designed for asymmetric synthesis of 1,3-disubstituted 2-vinylcyclopropanes. The allylides, generated in situ from the corresponding telluronium salt in the presence of different base, reacted with alpha,beta-unsaturated esters, ketones, and amides to afford cis-2-silylvinyl-trans-3-substituted or trans-2-silylvinyl-trans-3-substituted cyclopropane derivatives with high diastereoselectivity and excellent enantioselectivity in good to high yields. Thus, either one of the two diastereomers could be enantioselectively synthesized at will just by the choice of LiTMP/HMPA or LDA/LiBr. The first examples of catalytic ylide reaction for enantioselective synthesis of 1,3-disubstituted 2-vinylcyclopropanes with high distereoselectivity is also achieved.
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Affiliation(s)
- Wei-Wei Liao
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, China
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486
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Taylor RE, Engelhardt F, Schmitt M. Biosynthetic inspirations: cationic approaches to cyclopropane formation. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00880-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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487
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Larionov OV, Kozhushkov SI, Brandl M, de Meijere A. Rational synthesis of all the four stereoisomers of 3-(trans-2-aminocyclopropyl)alanine. MENDELEEV COMMUNICATIONS 2003. [DOI: 10.1070/mc2003v013n05abeh001817] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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