1
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Santana CG, Krische MJ. From Hydrogenation to Transfer Hydrogenation to Hydrogen Auto-Transfer in Enantioselective Metal-Catalyzed Carbonyl Reductive Coupling: Past, Present, and Future. ACS Catal 2021; 11:5572-5585. [PMID: 34306816 PMCID: PMC8302072 DOI: 10.1021/acscatal.1c01109] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Atom-efficient processes that occur via addition, redistribution or removal of hydrogen underlie many large volume industrial processes and pervade all segments of chemical industry. Although carbonyl addition is one of the oldest and most broadly utilized methods for C-C bond formation, the delivery of non-stabilized carbanions to carbonyl compounds has relied on premetalated reagents or metallic/organometallic reductants, which pose issues of safety and challenges vis-à-vis large volume implementation. Catalytic carbonyl reductive couplings promoted via hydrogenation, transfer hydrogenation and hydrogen auto-transfer allow abundant unsaturated hydrocarbons to serve as substitutes to organometallic reagents, enabling C-C bond formation in the absence of stoichiometric metals. This perspective (a) highlights past milestones in catalytic hydrogenation, hydrogen transfer and hydrogen auto-transfer, (b) summarizes current methods for catalytic enantioselective carbonyl reductive couplings, and (c) describes future opportunities based on the patterns of reactivity that animate transformations of this type.
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Affiliation(s)
| | - Michael J Krische
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
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2
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Meyer CC, Ortiz E, Krische MJ. Catalytic Reductive Aldol and Mannich Reactions of Enone, Acrylate, and Vinyl Heteroaromatic Pronucleophiles. Chem Rev 2020; 120:3721-3748. [PMID: 32191438 PMCID: PMC7904107 DOI: 10.1021/acs.chemrev.0c00053] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Catalytic reductive coupling of enone, acrylate, or vinyl heteroaromatic pronucleophiles with carbonyl or imine partners offers an alternative to base-mediated enolization in aldol- and Mannich-type reactions. In this review, direct catalytic reductive aldol and Mannich reactions are exhaustively catalogued on the basis of metal or organocatalyst. Stepwise processes involving enone conjugate reduction to form discrete enol or (metallo)enolate derivatives followed by introduction of carbonyl or imine electrophiles and aldol reactions initiated via enone conjugate addition are not covered.
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Affiliation(s)
- Cole C. Meyer
- University of Texas at Austin, Department of Chemistry, Welch Hall
(A5300), 105 E 24 St., Austin, TX 78712, USA
| | - Eliezer Ortiz
- University of Texas at Austin, Department of Chemistry, Welch Hall
(A5300), 105 E 24 St., Austin, TX 78712, USA
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry, Welch Hall
(A5300), 105 E 24 St., Austin, TX 78712, USA
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3
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Poeschl A, Mountford DM, Hider RC, Cilibrizzi A. Synthetic Approaches for Piperidone-Based Templates as Scaffolds to Access Chirally Enriched Donepezil Analogues. ACS OMEGA 2020; 5:2378-2396. [PMID: 32064399 PMCID: PMC7017409 DOI: 10.1021/acsomega.9b03808] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 12/31/2019] [Indexed: 06/10/2023]
Abstract
A concise and high-yielding double aza-Michael reaction is presented as an atom-efficient method to access chiral 2-substituted 4-piperidone building blocks from divinyl ketones. The piperidones were further converted into analogues of donepezil, an acetylcholinesterase inhibiting drug used in the treatment of Alzheimer's disease. The donepezil analogues were obtained as inseparable diastereomeric mixtures with resolved stereochemistry in position 2 of the piperidine ring. Biological evaluation of the acetylcholinesterase inhibition by these analogues provides a new insight into structure-activity relationship studies with regard to donepezil's piperidine moiety toward stereochemical enhancement.
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4
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Agirre M, Henrion S, Rivilla I, Miranda JI, Cossío FP, Carboni B, Villalgordo JM, Carreaux F. 1,3-Dioxa-[3,3]-sigmatropic Oxo-Rearrangement of Substituted Allylic Carbamates: Scope and Mechanistic Studies. J Org Chem 2018; 83:14861-14881. [PMID: 30457341 DOI: 10.1021/acs.joc.8b01320] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An unexpected 1,3-dioxa-[3,3]-sigmatropic rearrangement during the treatment of aryl- and alkenyl-substituted allylic alcohols with activated isocyanates is reported. The reorganization of bonds is highly dependent on the electron density of the aromatic ring and the nature of isocyanate used. This metal-free tandem reaction from branched allyl alcohols initiated by a carbamoylation reaction and followed by a sigmatropic rearrangement thus offers a new access to ( E)-cinnamyl and conjugated ( E, E)-diene carbamates, such as N-acyl and N-sulfonyl derivatives. A computational study was conducted in order to rationalize this phenomenon, and a rearrangement progress kinetic analysis was performed.
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Affiliation(s)
- Maddalen Agirre
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química , Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC) , P° Manuel Lardizabal 3 , 20018 San Sebastián/Donostia , Spain
| | - Sylvain Henrion
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226 , 263, avenue du Général Leclerc, Campus de Beaulieu , F-35000 Rennes , France
| | - Ivan Rivilla
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química , Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC) , P° Manuel Lardizabal 3 , 20018 San Sebastián/Donostia , Spain
| | - José I Miranda
- SGIker NMR Facility , Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU) , Avda. Tolosa 72 , E-20018 San Sebastián/Donostia , Spain
| | - Fernando P Cossío
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química , Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC) , P° Manuel Lardizabal 3 , 20018 San Sebastián/Donostia , Spain
| | - Bertrand Carboni
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226 , 263, avenue du Général Leclerc, Campus de Beaulieu , F-35000 Rennes , France
| | - José M Villalgordo
- VillaPharma Research, Parque Tecnológico de Fuente Alamo , Ctra. El Estrecho-Lobosillo, Av. Azul , 30320 Murcia , Spain
| | - François Carreaux
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226 , 263, avenue du Général Leclerc, Campus de Beaulieu , F-35000 Rennes , France
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5
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DePorre YC, Annand JR, Bar S, Schindler CS. Lewis-Base-Catalyzed Reductive Aldol Reaction To Access Quaternary Carbons. Org Lett 2018; 20:2580-2584. [PMID: 29648840 DOI: 10.1021/acs.orglett.8b00507] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A synthetic method for the efficient construction of β-hydroxylactones and lactams bearing α-quaternary carbon centers is described. This transformation relies on an electronically differentiated Lewis base catalyst, which is uniquely capable of promoting a reductive aldol reaction of α,α-disubstituted and α,α,β-trisubstituted enones. This approach provides a valuable synthetic alternative for carbon-carbon bond formation in complex molecular settings due to its orthogonal reactivity compared to that of traditional aldol reactions. Based on this method described herein, lactones, lactams, and morpholine amides bearing α-quaternary carbon centers are accessible in yields up to 85% and 50:1 dr.
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Affiliation(s)
- Yvonne C DePorre
- Department of Chemistry, Willard Henry Dow Laboratory , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
| | - James R Annand
- Department of Chemistry, Willard Henry Dow Laboratory , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Sukanta Bar
- Department of Chemistry, Willard Henry Dow Laboratory , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Corinna S Schindler
- Department of Chemistry, Willard Henry Dow Laboratory , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
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Shirinian VZ, Lvov AG, Yadykov AV, Yaminova LV, Kachala VV, Markosyan AI. Triaryl-Substituted Divinyl Ketones Cyclization: Nazarov Reaction versus Friedel-Crafts Electrophilic Substitution. Org Lett 2016; 18:6260-6263. [PMID: 27978676 DOI: 10.1021/acs.orglett.6b03023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The acid-catalyzed cyclization of a wide range of triaryl-substituted divinyl ketones has been studied. It was found that the reaction pathway strongly depends on the nature of the aryl substituent at the α-position to the carbonyl group. An electron-rich aromatic substituent promotes the reaction to proceed through the intramolecular Friedel-Crafts electrophilic substitution giving dihydronaphthalene derivatives. In contrast, the presence of an electron-deficient substituent is favorable for the Nazarov 4π-conrotatory cyclization yielding triaryl-substituted cyclopentenones. The electrophilic substitution reaction was applied to thiophene and thiazole derivatives.
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Affiliation(s)
| | - Andrey G Lvov
- N. D. Zelinsky Institute of Organic Chemistry, RAS , Moscow 119991, Russia
| | - Anton V Yadykov
- N. D. Zelinsky Institute of Organic Chemistry, RAS , Moscow 119991, Russia.,Higher Chemical Colleges, D.I. Mendeleev University of Chemical Technology of Russia , Moscow 125047, Russia
| | - Liana V Yaminova
- N. D. Zelinsky Institute of Organic Chemistry, RAS , Moscow 119991, Russia.,D.I. Mendeleev University of Chemical Technology of Russia , Moscow 125047, Russia
| | - Vadim V Kachala
- N. D. Zelinsky Institute of Organic Chemistry, RAS , Moscow 119991, Russia
| | - Ashot I Markosyan
- Scientific Technological Center of Organic and Pharmaceutical Chemistry, NAS RA , Yerevan 0014, Republic of Armenia
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Nuhant P, Allais C, Roush WR. Diisopinocampheylborane-Mediated Reductive Aldol Reactions: Highly Enantio- and Diastereoselective Synthesis ofsynAldols fromN-Acryloylmorpholine. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302535] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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8
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Nuhant P, Allais C, Roush WR. Diisopinocampheylborane-mediated reductive aldol reactions: highly enantio- and diastereoselective synthesis of syn aldols from N-acryloylmorpholine. Angew Chem Int Ed Engl 2013; 52:8703-7. [PMID: 23818095 DOI: 10.1002/anie.201302535] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Philippe Nuhant
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, 3A2, Jupiter, FL 33458, USA
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9
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Zeng X. Recent Advances in Catalytic Sequential Reactions Involving Hydroelement Addition to Carbon–Carbon Multiple Bonds. Chem Rev 2013; 113:6864-900. [DOI: 10.1021/cr400082n] [Citation(s) in RCA: 374] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Xiaoming Zeng
- Center for
Organic Chemistry, Frontier Institute of
Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi, 710054, P. R. China
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10
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Ou J, Wong WT, Chiu P. Reductive aldol cyclizations of unsaturated thioester derivatives of 1,3-cyclopentanedione catalyzed by chiral copper hydrides. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.07.057] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Deschamp J, Hermant T, Riant O. An easy route toward enantio-enriched polycyclic derivatives via an asymmetric domino conjugate reduction–aldol cyclization catalyzed by a chiral Cu(I) complex. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.07.039] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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12
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Das J, Le Cavelier F, Rouden J, Blanchet J. Expanding the Scope of the Direct Regiospecific Asymmetric Aldol Reaction to Enones and Dienones Catalyzed by a BINOL-Derived Brønsted Acid. European J Org Chem 2011. [DOI: 10.1002/ejoc.201101282] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Li N, Ou J, Miesch M, Chiu P. Conjugate reduction and reductive aldol cyclization of α,β-unsaturated thioesters catalyzed by (BDP)CuH. Org Biomol Chem 2011; 9:6143-7. [DOI: 10.1039/c1ob05352c] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Hong JT, Wang X, Kim JH, Kim K, Yun H, Jang HY. Platinum(II)-Catalyzed Allylation of CO and CN Bonds under Hydrogenation Conditions. Adv Synth Catal 2010. [DOI: 10.1002/adsc.201000648] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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15
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Williams VM, Kong JR, Ko BJ, Mantri Y, Brodbelt JS, Baik MH, Krische MJ. ESI-MS, DFT, and synthetic studies on the H(2)-mediated coupling of acetylene: insertion of C=X bonds into rhodacyclopentadienes and Brønsted acid cocatalyzed hydrogenolysis of organorhodium intermediates. J Am Chem Soc 2010; 131:16054-62. [PMID: 19845357 DOI: 10.1021/ja906225n] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The catalytic mechanism of the hydrogen-mediated coupling of acetylene to carbonyl compounds and imines has been examined using three techniques: (a) ESI-MS and ESI-CAD-MS analyses, (b) computational modeling, and (c) experiments wherein putative reactive intermediates are diverted to alternate reaction products. ESI-MS analysis of reaction mixtures from the hydrogen-mediated reductive coupling of acetylene to alpha-ketoesters or N-benzenesulfonyl aldimines corroborate a catalytic mechanism involving C horizontal lineX (X = O, NSO(2)Ph) insertion into a cationic rhodacyclopentadiene obtained by way of acetylene oxidative dimerization with subsequent Brønsted acid cocatalyzed hydrogenolysis of the resulting oxa- or azarhodacycloheptadiene. Hydrogenation of 1,6-diynes in the presence of alpha-ketoesters provides analogous coupling products. ESI mass spectrometric analysis again corroborates a catalytic mechanism involving carbonyl insertion into a cationic rhodacyclopentadiene. For all ESI-MS experiments, the structural assignments of ions are supported by multistage collisional activated dissociation (CAD) analyses. Further support for the proposed catalytic mechanism derives from experiments aimed at the interception of putative reactive intermediates and their diversion to alternate reaction products. For example, rhodium-catalyzed coupling of acetylene to an aldehyde in the absence of hydrogen or Brønsted acid cocatalyst provides the corresponding (Z)-butadienyl ketone, which arises from beta-hydride elimination of the proposed oxarhodacycloheptadiene intermediate, as corroborated by isotopic labeling. Additionally, the putative rhodacyclopentadiene intermediate obtained from the oxidative coupling of acetylene is diverted to the product of reductive [2 + 2 + 2] cycloaddition when N-p-toluenesulfonyl-dehydroalanine ethyl ester is used as the coupling partner. The mechanism of this transformation also is corroborated by isotopic labeling. Computer model studies based on density functional theory (DFT) support the proposed mechanism and identify Brønsted acid cocatalyst assisted hydrogenolysis to be the most difficult step. The collective studies provide new insight into the reactivity of cationic rhodacyclopentadienes, which should facilitate the design of related rhodium-catalyzed C-C couplings.
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Affiliation(s)
- Vanessa M Williams
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA
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Mizuno M, Inoue H, Naito T, Zhou L, Nishiyama H. Asymmetric, Regioselective Direct Aldol Coupling of Enones and Aldehydes with Chiral Rhodium(bis-oxazolinylphenyl) Catalysts. Chemistry 2009; 15:8985-8. [DOI: 10.1002/chem.200901329] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Skucas E, Zbieg JR, Krische MJ. anti-Aminoallylation of aldehydes via ruthenium-catalyzed transfer hydrogenative coupling of sulfonamido allenes: 1,2-aminoalcohols. J Am Chem Soc 2009; 131:5054-5. [PMID: 19317402 PMCID: PMC2676672 DOI: 10.1021/ja900827p] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ruthenium-catalyzed transfer hydrogenation of N-sulfonamido allene 1e in the presence of aromatic aldehydes 2a-f, alpha,beta-unsaturated aldehydes 2g-i, and aliphatic aldehydes 2j-l results in reductive coupling to furnish the corresponding anti-aminoallylation products 3a-l. Reductive coupling of allenamide 1e to aldehyde 2a conducted using 2-propanol-d(8) as the terminal reductant delivers deuterio-3a. The observed pattern of deuterium incorporation suggests reversible allene hydrometalation with incomplete regioselectivity in advance of carbonyl addition. A survey of monosubstituted allenes 1f-i was conducted. High levels of anti-diastereoselectivity were observed only when tert-butyl allene 1f was used. This protocol represents an alternative to the use of amino-substituted allylborane reagents in carbonyl aminoallylation and avoids the use of stoichiometric metallic reagents.
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Affiliation(s)
- Eduardas Skucas
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA
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C. Majumdar K, Debnath P, Roy B. Metal-Catalyzed Heterocyclization: Formation of Five- and Six-Membered Oxygen Heterocycles through Carbon-Oxygen Bond Forming Reactions. HETEROCYCLES 2009. [DOI: 10.3987/rev-09-656] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Ghosh AK, Kass J, Anderson DD, Xu X, Marian C. L-selectride-mediated highly diastereoselective asymmetric reductive aldol reaction: access to an important subunit for bioactive molecules. Org Lett 2008; 10:4811-4. [PMID: 18831554 DOI: 10.1021/ol801971t] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
L-selectride reduction of a chiral or achiral enone followed by reaction of the resulting enolate with optically active alpha-alkoxy aldehydes proceeded with excellent diastereoselectivity. The resulting alpha,alpha-dimethyl-beta-hydroxy ketones are inherent to a variety of biologically active natural products.
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Affiliation(s)
- Arun K Ghosh
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
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20
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Komanduri V, Grant CD, Krische MJ. Branch-selective reductive coupling of 2-vinyl pyridines and imines via rhodium catalyzed C-C bond forming hydrogenation. J Am Chem Soc 2008; 130:12592-3. [PMID: 18759388 PMCID: PMC2844715 DOI: 10.1021/ja805056g] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydrogenation of 2-vinyl azines 1a-1e in the presence of N-arylsulfonyl imines 2a-2l at ambient temperature and pressure employing cationic rhodium catalysts ligated by tri-2-furylphosphine results in regioselective reductive coupling to furnish branched products of imine addition 3a-3v, which embody modest to high levels of syn-diastereoselectivity. Catalytic coupling of 6-bromo-2-vinylpyridine 1a to imine 2l under an atmosphere of elemental deuterium provides deuterio-3l, with deuterium exclusively at the former beta-position of the vinyl moiety. These data are consistent with a catalytic mechanism involving oxidative coupling of the vinyl azine and imine partners to furnish a cationic aza-rhodacyclopentane, which upon deuteriolytic cleavage releases the adduct and regenerates cationic rhodium(I) to close the catalytic cycle. These studies represent the first metal catalyzed reductive C-C couplings of vinyl azines.
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Affiliation(s)
- Venukrishnan Komanduri
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
| | - Christopher D. Grant
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
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Diastereo- and Enantioselective Reductive Aldol Addition of Vinyl Ketones via Catalytic Hydrogenation. SYNTHESIS-STUTTGART 2008; 2008:2669-2679. [PMID: 21866204 DOI: 10.1055/s-2008-1067220] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
An overview of studies on hydrogenative reductive aldol addition is presented. By simply hydrogenating enones in the presence of aldehydes at ambient temperature and pressure, aldol adducts are generated under neutral conditions in the absence of any stoichiometric byproducts. Using cationic rhodium complexes modified by tri(2-furyl)phosphine, highly syn-diastereoselective reductive aldol additions of vinyl ketones are achieved. Finally, using novel monodentate TADDOL-like phosphonite ligands, the first highly diastereo- and enantioselective reductive aldol couplings of vinyl ketones were devised. These studies, along with other works from our laboratory, demonstrate that organometallics arising transiently in the course of catalytic hydrogenation offer byproduct-free alternatives to preformed organometallic reagents employed in classical carbonyl addition processes.
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22
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Synthesis of six-membered oxygenated heterocycles through carbon–oxygen bond-forming reactions. Tetrahedron 2008. [DOI: 10.1016/j.tet.2007.11.092] [Citation(s) in RCA: 212] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Bee C, Han SB, Hassan A, Iida H, Krische MJ. Diastereo- and enantioselective hydrogenative aldol coupling of vinyl ketones: design of effective monodentate TADDOL-like phosphonite ligands. J Am Chem Soc 2008; 130:2746-7. [PMID: 18266373 DOI: 10.1021/ja710862u] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report the first enantioselective reductive aldol couplings of vinyl ketones, which were achieved through the design of a novel monodentate TADDOL-like phosphonite ligand. Specifically, hydrogenation of commercially available methyl vinyl ketone (MVK) or ethyl vinyl ketone (EVK) in the presence of aldehydes 1a-7a using cationic rhodium catalysts modified by chiral TADDOL-like phosphonite ligands AP-I and AP-IV produces aldol adducts 1b-7b and 1c-7c with excellent control of relative and absolute stereochemistry. The absolute stereochemical assignments of the aldol adducts are made in analogy to that determined for the 5-bromophthalimido derivative of aldol adduct 1b and the 2-bromo-5-nitrobenzoate of 3b, which were established by single-crystal X-ray diffraction analysis using the anomalous dispersion method.
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Affiliation(s)
- Cisco Bee
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, Texas 78712, USA
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25
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Catalytic Reductive Coupling of Alkenes and Alkynes to Carbonyl Compounds and Imines Mediated by Hydrogen. Top Curr Chem (Cham) 2007. [DOI: 10.1007/128_2007_122] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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