101
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Lysenko IL, Oh HS, Cha J. Diastereoselective Prins-type reaction of cycloalkenylcyclopropanol silyl ethers and alpha,beta-unsaturated aldehyde acetals. J Org Chem 2007; 72:7903-8. [PMID: 17850161 PMCID: PMC2597285 DOI: 10.1021/jo071272o] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electrophilic addition of 1-(1-cyclohexenyl)-1-cyclopropanol trimethylsilyl ether to alpha,beta-unsaturated aldehyde acetals under Lewis acidic conditions proceeds with good to excellent diastereoselectivity to afford spirocyclobutanones containing three contiguous stereocenters. A convenient entry to enantioselective syntheses is available by use of a nonracemic C2-symmetric acetal. Elaboration of the resulting adducts provides ready access to medium-sized carbocycles.
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102
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)01371-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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103
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)00834-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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104
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Breit B, Demel P, Grauer D, Studte C. Stereospecific and stereodivergent construction of tertiary and quaternary carbon centers through switchable directed/nondirected allylic substitution. Chem Asian J 2007; 1:586-97. [PMID: 17441097 DOI: 10.1002/asia.200600100] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study introduces the ortho-diphenylphosphanylbenzoate (o-DPPB)/o-DPPB oxide system as a switchable directing/nondirecting leaving group in a copper-mediated allylic substitution with Grignard and organozinc reagents. With this system, the regioselective, stereospecific, and stereodivergent construction of quaternary as well as tertiary carbon centers is possible in a reliable and predictable fashion. Starting from one substrate enantiomer, both optical antipodes of the substitution products are readily available. Hence, this methodology features reversed polarity in comparison to established enolate alkylation chemistry and may be an interesting alternative, particularly for the construction of quaternary stereogenic carbon centers.
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Affiliation(s)
- Bernhard Breit
- Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstr. 21, 79104 Freiburg, Germany.
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105
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Satoh T, Endo J, Ota H, Chyouma T. A synthesis, including asymmetric synthesis, of α-quaternary α-amino aldehydes from ketones and chloromethyl p-tolyl sulfoxide via sulfinylaziridines. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.03.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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106
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)00205-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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107
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Snape TJ. Recent advances in the semi-pinacol rearrangement of α-hydroxy epoxides and related compounds. Chem Soc Rev 2007; 36:1823-42. [PMID: 18213988 DOI: 10.1039/b709634h] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Timothy J Snape
- Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, UK.
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108
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Mikami K, Akiyama K. Pd(II)-Catalyzed Enantioselective Intramolecular Heck-Type Reaction to Construct Chiral Sulfonamide Rings. HETEROCYCLES 2007. [DOI: 10.3987/com-07-s(w)74] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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109
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Langner M, Rémy P, Bolm C. Highly modular synthesis of C1-symmetric aminosulfoximines and their use as ligands in copper-catalyzed asymmetric Mukaiyama-aldol reactions. Chemistry 2006; 11:6254-65. [PMID: 16075444 DOI: 10.1002/chem.200500497] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The development of C1-symmetric aminosulfoximines, their highly modular synthesis, and their application in enantioselective copper-catalyzed Mukaiyama-type aldol reactions between pyruvates and enolsilanes is described. In this context, the influence of the ligand architecture as well as the optimization of the reaction conditions are discussed. In detail, the dependence of the catalyst efficiency on the solvent, the metal source and the temperature are reported, and an interesting additive effect is highlighted. Furthermore, the substrate scope will be presented. With the optimized catalyst system, a number of aldol products with quaternary stereogenic centers have been obtained in high yields and with enantiomeric excesses up to 99 %.
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Affiliation(s)
- Martin Langner
- Institut für Organische Chemie der Rheinisch-Westfälischen Technischen Hochschule Aachen, Germany
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110
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Marek I, Sklute G. Creation of quaternary stereocenters in carbonyl allylation reactions. Chem Commun (Camb) 2006:1683-91. [PMID: 17457409 DOI: 10.1039/b615042j] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Despite the advances in stereoselective carbonyl allylation reactions, the creation of quaternary stereocenters in the addition of 3,3'-disubstituted allylmetals to aldehydes is still a challenging issue. This feature article describes the most powerful approaches that have been devised to address this problem.
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Affiliation(s)
- Ilan Marek
- The Mallat Family Laboratory of Organic Chemistry, The Lise Meitner-Minerva Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa, 32 000, Israel.
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111
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)01801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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112
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Enantioselective homoallyl-cyclopropanation of dibenzylideneacetone by modified allylindium halide reagents—rapid access to enantioenriched 1-styryl-norcarene. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.05.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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113
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Sieburth SM, Langevine CN, Dardaris DM. Organosilane insecticides. Part II: Chemistry and structure-activity relationships. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/ps.2780280309] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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114
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)00771-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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115
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Taber DF, He Y. Opening of aryl-substituted epoxides to form quaternary stereogenic centers: synthesis of (-)-mesembrine. J Org Chem 2006; 70:7711-4. [PMID: 16149803 PMCID: PMC3248819 DOI: 10.1021/jo0511039] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Cycloalkanones are easily converted into aryl-substituted cyclic alkenes by the addition of an aryl Grignard reagent followed by dehydration. These alkenes are good substrates for asymmetric epoxidation. We have found that the addition of allylic and benzylic Grignard reagents can occur preferentially at the benzylic position of the derived epoxides to give the quaternary stereogenic center. This approach led to a short synthesis of the nanomolar serotonin re-uptake inhibitor (-)-mesembrine.
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Affiliation(s)
- Douglass F Taber
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
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116
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Enders D, Knopp M, Runsink J, Raabe G. The First Asymmetric Carroll Rearrangement Diastereo- and Enantioselective Synthesis of Polyfunctional Ketones with Vicinal Quaternary and Tertiary Stereogenic Centers. European J Org Chem 2006. [DOI: 10.1002/jlac.199619960708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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117
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Shaw SA, Aleman P, Christy J, Kampf JW, Va P, Vedejs E. Enantioselective TADMAP-catalyzed carboxyl migration reactions for the synthesis of stereogenic quaternary carbon. J Am Chem Soc 2006; 128:925-34. [PMID: 16417383 PMCID: PMC2532525 DOI: 10.1021/ja056150x] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The chiral, nucleophilic catalyst TADMAP [1, 3-(2,2,2-triphenyl-1-acetoxyethyl)-4-(dimethylamino)pyridine] has been prepared from 3-lithio-4-(dimethylamino)pyridine (5) and triphenylacetaldehyde (3), followed by acylation and resolution. TADMAP catalyzes the carboxyl migration of oxazolyl, furanyl, and benzofuranyl enol carbonates with good to excellent levels of enantioselection. The oxazole reactions are especially efficient and are used to prepare chiral lactams (23) and lactones (30) containing a quaternary asymmetric carbon. TADMAP-catalyzed carboxyl migrations in the indole series are relatively slow and proceed with inconsistent enantioselectivity. Modeling studies (B3LYP/6-31G*) have been used in qualitative correlations of catalyst conformation, reactivity, and enantioselectivity.
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Affiliation(s)
- Scott A. Shaw
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109,
| | - Pedro Aleman
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109,
| | - Justin Christy
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109,
| | - Jeff W. Kampf
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109,
| | - Porino Va
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109,
| | - Edwin Vedejs
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109,
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118
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Enders D, Zamponi A, Schäfer T, Nübling C, Eichenauer H, Demir AS, Raabe G. Enantioselective Synthesis of Polyfunctional Small Building Blocks with a Quaternary Stereogenic Center. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cber.19941270922] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dieter Enders
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
| | - Andreas Zamponi
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
| | - Thomas Schäfer
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
| | - Christoph Nübling
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
| | - Herbert Eichenauer
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
| | - Ayhan Sitki Demir
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
| | - Gerhard Raabe
- Institut für Organische Chemie der Technischen Hochschule Aachen, Professor‐Pirlet‐Straße 1, D‐52074 Aachen, Germany
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119
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120
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121
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Saba A, Muroni D, Culeddu N. Concise Highly Enantioselective Cascade Synthesis of Azacyclooctene Alkaloids with a Quaternary Stereocenter. HETEROCYCLES 2006. [DOI: 10.3987/com-05-10567] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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122
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Mikami K, Itoh Y. Metal enolates ofα-CF3 ketones: theoretical guideline, direct generation, and synthetic use. CHEM REC 2006; 6:1-11. [PMID: 16470799 DOI: 10.1002/tcr.20066] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The difficulty as well as the significance of the direct generation of metal enolates of alpha-CF(3) ketones cannot be easily understood by chemists unfamiliar with F. In sharp contrast to the sunny side of non-F, hydrocarbon chemistry, F chemistry has long been overshadowed. Metal enolates of carbonyl compounds are synthetically important in C-C bond-forming reactions. However, the metal enolates of fluorinated carbonyl compounds have been severely limited to alpha-F metal enolates. Alpha-CF(3) metal enolates have generally been recognized as unstable and difficult to prepare because of the facile beta-M-F elimination. However, we have developed a direct generation and synthetic application of alpha-CF(3) metal enolates. Therefore, the present results regarding the direct generation and synthetic use of metal enolates of alpha-CF(3) ketones might be recognized as a real breakthrough for the general use of metal enolates in F chemistry.
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Affiliation(s)
- Koichi Mikami
- Department of Applied Chemistry, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552.
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123
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Zhou H, Liao X, Yin W, Ma J, Cook JM. General Approach for the Synthesis of 12-Methoxy-Substituted Sarpagine Indole Alkaloids Including (−)-12-Methoxy-Nb-methylvoachalotine, (+)-12-Methoxy-Na-methylvellosimine, (+)-12-Methoxyaffinisine, and (−)-Fuchsiaefoline. J Org Chem 2005; 71:251-9. [PMID: 16388644 DOI: 10.1021/jo052081t] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structures: see text] The enantiospecific synthesis of 7-methoxy-D-tryptophan ethyl ester was completed by combination of the Larock heteroannulation process with a Schöllkopf-based chiral auxiliary in good yield. This ester was then employed in the first regiospecific, stereospecific total synthesis of (+)-12-methoxy-N(a)-methylvellosimine, (+)-12-methoxyaffinisine, (-)-fuchsiaefoline, and 12-methoxy-N(b)-methylvoachalotine in excellent overall yield. The asymmetric Pictet-Spengler reaction and enolate-driven palladium-catalyzed cross-coupling processes served as key steps. The quaternary center at C16 of 12-methoxy-N(b)-methylvoachalotine was established via the Tollens reaction between (+)-12-methoxy-N(a)-methylvellosimine and formaldehyde to form diol 17. The two prochiral primary alcohols in diol 17 were differentiated by the oxidative cyclization(DDQ) of the hydroxyl group at the axial position of 17 with the benzylic postion at [C6] to form a cyclic ether [C6-O17]. After oxidative formation of the alpha-ester at C16, the ether bond was reductively cleaved with TFA/Et3SiH in high yield. The DDQ-mediated oxidative cyclization and TFA/Et3SiH reductive cleavage served as protection/deprotection steps in order to provide a versatile entry into the voachalotine alkaloids.
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Affiliation(s)
- Hao Zhou
- Department of Chemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, USA
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124
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Dondoni A, Catozzi N, Marra A. Concise and Practical Synthesis of C-Glycosyl Ketones from Sugar Benzothiazoles and Their Transformation into Chiral Tertiary Alcohols. J Org Chem 2005; 70:9257-68. [PMID: 16268598 DOI: 10.1021/jo051377w] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[Reaction: see text]. A collection of 13 unsymmetrical ketones, each one featuring a sugar (d-glucosyl, d-galactosyl, d-mannosyl, and l-fucosyl) and an aglycone moiety (phenyl, 2-thiazolyl, TMS-ethynyl, allyl, and 1-propenyl) was prepared by a uniform route based on the use of benzothiazole as a carbonyl group equivalent. Succinctly, C-glycosylbenzothiazoles readily prepared by addition of 2-lithiobenzothiazole to sugar lactones and deoxygenation, were subjected to a one-pot reaction sequence involving N-methylation of the heterocyclic ring by MeOTf, treatment of the N-methylbenzothiazolium salt with a Grignard reagent, and HgCl(2)-promoted hydrolysis of the benzothiazoline thus formed. The resulting ketones were isolated in yields varying from 35 to 80%. Treatment of the sugar ketones with various organometals containing the phenyl, 2-thiazolyl, TMS-ethynyl, or ethynyl group as a substituent afforded chiral tertiary alcohols. These addition reactions were highly stereoselective as observed by crude NMR analysis and isolation of a single epimer in high yield in each case examined. However, because of the complexity of the reagents involved, the stereochemical outcome of these reactions appears to be difficult to rationalize by simple classical steric models, thus, ab initio studies taking into account the role of the sugar fragment are advisable. An interesting synthetic elaboration of a propargylic alcohol containing the thiazole ring into a propargylic alcohol bearing the formyl and carboxylate groups is reported.
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Affiliation(s)
- Alessandro Dondoni
- Dipartimento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara, Via L. Borsari 46, 44100-Ferrara, Italy.
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125
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126
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Fennie MW, DiMauro EF, O'Brien EM, Annamalai V, Kozlowski MC. Mechanism and scope of salen bifunctional catalysts in asymmetric aldehyde and α-ketoester alkylation. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.03.117] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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127
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Reetz MT. Organotitanium reagents in organic synthesis a simple means to adjust reactivity and selectivity of carbanions. ACTA ACUST UNITED AC 2005. [DOI: 10.1007/3-540-11766-0_1] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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128
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Kreidler B, Baro A, Frey W, Christoffers J. Generation of Quaternary Stereocenters by Asymmetric Michael Reactions: Enamine Regiochemistry as Configuration Switch. Chemistry 2005; 11:2660-7. [PMID: 15729681 DOI: 10.1002/chem.200401223] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Regioselective enamine formation from cyclic beta-diketones 1 is obtained by the appropriate choice of activating agent: Brønsted acid catalyzed condensation gives endocyclic enamines 3 as the thermodynamically favored products. Activation with Lewis acid BF(3).OEt(2) affords betaines 8 as intermediate products, which can be reacted with L-valine diethylamide (2) to preferentially furnish exocyclic enamines 4 as kinetic products. Derivatives with quaternary stereocenters were accessible from both isomeric enamines by using asymmetric, copper(II)-catalyzed Michael reactions at ambient temperature. Both regioisomers afford the triketones 7 with the same constitution but bearing the opposite absolute configuration at the quaternary stereocenter. Thus, both enantiomers of the product are prepared by using the same chiral auxiliary derived from L-valine.
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Affiliation(s)
- Burkard Kreidler
- Institut für Organische Chemie der Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
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129
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Sugiyama S, Satoh T. Asymmetric synthesis of both enantiomers of esters and γ-lactones from optically active 1-chlorovinyl p-tolyl sulfoxides and lithium ester enolates with the formation of a tertiary or a quaternary carbon stereogenic center at the β-position. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.tetasy.2004.11.085] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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130
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131
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Enantioselective catalysis of carbonyl-ene and Friedel–Crafts reactions with trifluoropyruvate by ‘naked’ palladium(II) complexes with SEGPHOS ligands. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.10.022] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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132
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Kimura M, Yamazaki T, Kitazume T, Kubota T. Construction of Optically Active CF3-Containing Quaternary Carbon Centers via Stereospecific SN2‘ Reaction. Org Lett 2004; 6:4651-4. [PMID: 15575652 DOI: 10.1021/ol0481941] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Phosphates from 3-substituted 4,4,4-trifluorobut-2-en-1-ols were found to be effective for construction of CF3-containing quaternary carbon centers by way of Cu(I)-catalyzed Grignard reactions in the presence of catalytic amounts of CuCN and trimethylsilyl chloride (TMSCl) in an anti S(N)2' manner.
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Affiliation(s)
- Mitsuo Kimura
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
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133
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Langner M, Bolm C. C1-Symmetric Sulfoximines as Ligands in Copper-Catalyzed Asymmetric Mukaiyama-Type Aldol Reactions. Angew Chem Int Ed Engl 2004. [DOI: 10.1002/ange.200460953] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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134
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Langner M, Bolm C. C1-Symmetric Sulfoximines as Ligands in Copper-Catalyzed Asymmetric Mukaiyama-Type Aldol Reactions. Angew Chem Int Ed Engl 2004; 43:5984-7. [PMID: 15547912 DOI: 10.1002/anie.200460953] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Martin Langner
- Institut für Organische Chemie der Rheinisch-Westfälischen Technischen Hochschule Aachen, Professor-Pirlet-Strasse 1, 52056 Aachen, Germany
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135
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Forzato C, Nitti P, Pitacco G, Valentin E, Morganti S, Rizzato E, Spinelli D, Dell'Erba C, Petrillo G, Tavani C. Nitroalkylation and nitroalkenylation reactions of γ-lactone enolates. A facile ring switch from polysubstituted γ-lactones to polysubstituted γ-lactams. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.07.084] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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136
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Herradón B, Seebach D. Mono- and Dialkylation of Derivatives of (1R, 2S)-2-Hydroxycyclopentanecarboxylic Acid and -cyclohexanecarboxylic acidviabicyclic dioxanones: Selective generation of three contiguous stereogenic centers on a cyclohexane ring. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19890720410] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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137
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Dake GR, Fenster MDB, Fleury M, Patrick BO. Investigations of alpha-siloxy-epoxide ring expansions forming 1-azaspirocyclic ketones. J Org Chem 2004; 69:5676-83. [PMID: 15307739 DOI: 10.1021/jo049356+] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The construction of 1-azaspirocyclic cycloalkanones using a siloxy-epoxide semipinacol ring expansion process was examined. Functionalized 1-azaspiro[5.5]undecan-7-ones (1-azaspirocyclic cyclohexanones) proceeded in high chemical yields with complete diastereoselectivity using titanium tetrachloride as the Lewis acid promoter. The formation of functionalized 6-azaspiro[5.4]-decan-1-ones (1-azaspirocyclic cyclopentanones) proceeded in high chemical yield with little diastereoselectivity. Modification of reaction parameters such as the Lewis acid promoter or the nature of the silyl ether allowed for the preferential formation of either ("anti" or "syn" 1,2 alkyl shift) diastereomeric product. An explanation for the different reactivity profiles between the cyclobutanol silyl ethers and cyclopentanol silyl ethers is provided.
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Affiliation(s)
- Gregory R Dake
- Department of Chemistry, 2036 Main Mall, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
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138
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A concise highly enantioselective cascade synthesis of indolizidine alkaloids with a quaternary stereocenter. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.07.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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139
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2004. [DOI: 10.1016/s0040-4020(04)01396-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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140
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Kezuka S, Kanemoto K, Takeuchi R. Iridium complex-catalyzed method for the construction of a quaternary carbon center α to allene. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.07.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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141
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Sauer ELO, Barriault L. Highly Efficient Transfer of Chirality from Macrocyclic Conformation in the Tandem Oxy-Cope/Claisen/Ene Reaction. J Am Chem Soc 2004; 126:8569-75. [PMID: 15238016 DOI: 10.1021/ja048301m] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report three highly stereoselective pericyclic reactions occurring in cascade leading to the synthesis of Decalins skeletons possessing two contiguous quaternary centers. The tandem reaction is triggered by an oxy-Cope rearrangement to create in situ a 10-membered ring enol ether macrocyle 6, which immediately rearranges via a Claisen [3,3] shift to the corresponding E-cyclodec-6-en-1-one 7. The latter spontaneously cyclizes via a transannular ene reaction to produce Decalin 5. Analysis of the mechanism with respect to the origin of the high diastereoselectivity of the tandem oxy-Cope/Claisen/ene reaction is presented.
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Affiliation(s)
- Effiette L O Sauer
- Department of Chemistry, 10 Marie Curie, University of Ottawa, Ottawa, Canada K1N 6N5
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142
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The first enantiospecific total synthesis of a C-quaternary voachalotine alkaloid, (+)-dehydrovoachalotine. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.03.096] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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143
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Douglas CJ, Overman LE. Catalytic asymmetric synthesis of all-carbon quaternary stereocenters. Proc Natl Acad Sci U S A 2004; 101:5363-7. [PMID: 14724294 PMCID: PMC397386 DOI: 10.1073/pnas.0307113101] [Citation(s) in RCA: 744] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Only a few catalytic asymmetric C-C bond-forming reactions have been shown to be useful for constructing all-carbon quaternary stereocenters. This Perspective examines the current state of such methods.
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144
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Tetrahedron reports on organic chemistry. Tetrahedron 2004. [DOI: 10.1016/s0040-4020(04)00315-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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145
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Csákÿ AG, Mba M, Plumet J. Asymmetric synthesis of cyclopentenones with benzylic α-quaternary carbon stereogenic centres from furans. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.01.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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146
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Asymmetric catalysis of ene reactions with trifluoropyruvate catalyzed by dicationic palladium(II) complexes. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2003.10.137] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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147
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Barriault L, A. Farand J, Denissova I. Microwave Assisted Pericyclic Reactions in Cascade to Construct Decalin Frame- works Possessing Quaternary Centers. Scope and Limitations. HETEROCYCLES 2004. [DOI: 10.3987/com-03-s(p)72] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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148
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Ohno H, Hiramatsu K, Tanaka T. Asymmetric construction of quaternary carbon centers by titanium-mediated stereospecific allylation of 2,3-epoxy alcohol derivatives. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2003.10.112] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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149
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Satoh T, Fukuda Y. A new synthesis of enantiomerically pure α- and β-amino acid derivatives using aziridinyl anions. Tetrahedron 2003. [DOI: 10.1016/j.tet.2003.09.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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150
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)01884-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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