1
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Malik M, Senatore R, Langer T, Holzer W, Pace V. Base-mediated homologative rearrangement of nitrogen-oxygen bonds of N-methyl- N-oxyamides. Chem Sci 2023; 14:10140-10146. [PMID: 37772102 PMCID: PMC10530184 DOI: 10.1039/d3sc03216g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 08/26/2023] [Indexed: 09/30/2023] Open
Abstract
Due to the well known reactivity of C(O)-N functionalities towards canonical C1-homologating agents (e.g. carbenoids, diazomethane, ylides), resulting in the extrusion of the N-centered fragment en route to carbonyl compounds, formal C1-insertions within N-O bonds still remain obscure. Herein, we document the homologative transformation of N-methyl-N-oxyamides - with high tolerance for diverse O-substituents - into N-acyl-N,O-acetals. Under controlled basic conditions, the N-methyl group of the same starting materials acts as a competent precursor of the methylene synthon required for the homologation. The logic is levered on the formation of an electrophilic iminium ion (via N-O heterolysis) susceptible to nucleophilic attack by the alkoxide previously expulsed. The procedure documents genuine chemocontrol and flexibility, as judged by the diversity of substituents placed on both amide and nitrogen linchpins. The mechanistic rationale was validated through experiments conducted on D-labeled materials which unambiguously attributed the origin of the methylene fragment to the N-methyl group of the starting compounds.
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Affiliation(s)
- Monika Malik
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna Josef-Holaubek-Platz 2 1090 Vienna Austria
| | - Raffaele Senatore
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna Josef-Holaubek-Platz 2 1090 Vienna Austria
| | - Thierry Langer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna Josef-Holaubek-Platz 2 1090 Vienna Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna Josef-Holaubek-Platz 2 1090 Vienna Austria
| | - Vittorio Pace
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna Josef-Holaubek-Platz 2 1090 Vienna Austria
- Department of Chemistry, University of Turin Via Giuria 7 10125 Turin Italy
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2
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Silambarasan K, Kesavulu G, Reddy AA, Prasad KR. Diastereoselective Synthesis of trans-β-Amino Cyclohexyl Ketones and trans-3-Amino-4-acyl-tetrahydropyrans from Intramolecular C-Alkylation of ω-Halo-Substituted β-Sulfinamido Ketones. J Org Chem 2023; 88:2006-2022. [PMID: 36753743 DOI: 10.1021/acs.joc.2c02227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Reaction of ω-halo-substituted nonracemic β-sulfinamido ketones with NaH afforded the β-amino cyclohexyl ketones in excellent yields and diastereoselectivity, via an intramolecular C-alkylation, α to the carbonyl group. The reaction was found to be general and can be applied for the synthesis of different cyclohexyl amino ketones and tetrahydropyrans possessing amine and acyl substitutions.
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Affiliation(s)
| | - Gangarajulu Kesavulu
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
| | | | - Kavirayani R Prasad
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
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3
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Jang J, Kim DY. Electrochemical
N
‐Centered Radical Addition/Semipinacol Rearrangement Sequence of Alkenyl Cyclobutanols: Synthesis of β‐Amino Cyclic Ketones. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202200531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Affiliation(s)
- Jihoon Jang
- Department of Chemistry and Department of ICT Environmental Health System Soonchunhyang University Asan 31538 Chungnam Republic of Korea
| | - Dae Young Kim
- Department of Chemistry and Department of ICT Environmental Health System Soonchunhyang University Asan 31538 Chungnam Republic of Korea
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4
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Ma TC, Yao S, Qiao MM, Yuan F, Shi DQ, Xiao WJ. Photoredox-mediated N-centered radical addition/semipinacol rearrangement for the convenient synthesis of β-amino (spiro)cyclic ketones. Org Chem Front 2021. [DOI: 10.1039/d1qo00543j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A photoredox-mediated N-centered radical addition/semipinacol rearrangement cascade of cycloalkanol-substituted 1H-indenes or styrenes with N-arylsulfonyl protected 1-aminopyridinium salts for the efficient synthesis of β-amino (spiro)cyclic ketones is presented.
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Affiliation(s)
- Tian-Cong Ma
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan
| | - Sheng Yao
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan
| | - Ming-Ming Qiao
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan
| | - Fan Yuan
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan
| | - De-Qing Shi
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan
| | - Wen-Jing Xiao
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan
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5
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Panagiotou M, Demos V, Magriotis PΑ. Direct and practical Gilman-Speeter synthesis of 3,4-trisubstituted β-lactams via the Thorpe-Ingold effect. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152375] [Citation(s) in RCA: 2] [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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6
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Houghton MJ, Collum DB. Lithium Enolates Derived from Weinreb Amides: Insights into Five-Membered Chelate Rings. J Org Chem 2016; 81:11057-11064. [PMID: 27749060 PMCID: PMC5261255 DOI: 10.1021/acs.joc.6b02067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enolization of O-methyl hydroxamic acids (Weinreb amides) in tetrahydrofuran solution with lithium diisopropylamide affords predominantly tetrameric enolates. Aryl substituents on the enolates promote deaggregation. The aggregation states are assigned by using the method of continuous variation in conjunction with 6Li NMR spectroscopy. Decoalescence of the tetramer resonance below -100 °C shows considerable spectral complexity attributed to isomerism of the methoxy-based chelates. Density functional theory calculations were used to examine the consequences of the bite angle of five-membered chelates in cubic tetramers and resulting solvation numbers that were higher than anticipated.
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Affiliation(s)
- Michael J. Houghton
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301
| | - David B. Collum
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301
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7
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Wang YN, Sun GX, Qi G. β-Amino functionalization of cinnamic Weinreb amides in ionic liquid. Beilstein J Org Chem 2016; 12:2372-2377. [PMID: 28144305 PMCID: PMC5238596 DOI: 10.3762/bjoc.12.231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 10/24/2016] [Indexed: 11/23/2022] Open
Abstract
2-Ns-Protected β-amino Weinreb amides were synthesized by aminochlorination of α,β-unsaturated Weinreb amides in an ionic liquid, 1-n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIM][NTf2]). Processed without the use of metal catalysts or the need of an inert gas atmosphere, the presented process can be readily performed as a one-pot synthesis at room temperature. Moreover, the preparation has the distinct advantages of the use of 2-NsNCl2 as an inexpensive and stable nitrogen/halogen source and the ionic liquid as a recyclable reaction media. Nine examples were examined, and modest to good isolated chemical yields (40–83%) were obtained.
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Affiliation(s)
- Yi-Ning Wang
- School of Chemistry & Chemical Engineering, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China
| | - Guo-Xiang Sun
- School of Chemistry & Chemical Engineering, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China
| | - Gang Qi
- School of Chemistry & Chemical Engineering, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, China
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8
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Semina E, Žukauskaitė A, Šačkus A, De Kimpe N, Mangelinckx S. Selective Elaboration of Aminodiols towards Small Ring α- and β-Amino Acid Derivatives that Incorporate an Aziridine, Azetidine, or Epoxide Scaffold. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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9
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Davis FA. Heterocyclic synthesis using the intramolecular Mannich cyclization reaction and enantiopureN-sulfinyl β-amino carbonyl compounds. PHOSPHORUS SULFUR 2016. [DOI: 10.1080/10426507.2015.1065260] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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10
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Semina E, Colpaert F, Van Hecke K, De Kimpe N, Mangelinckx S. Asymmetric Synthesis of δ-Chloro-β-amino-N-sulfinyl Imidates as Versatile Chiral Building Blocks for the Synthesis of 2,3-Disubstituted Piperidines. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500466] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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11
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Kiss L, Cherepanova M, Fülöp F. Recent advances in the stereoselective syntheses of acyclic disubstituted β2,3-amino acids. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.01.060] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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12
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Romanens A, Bélanger G. Preparation of conformationally restricted β(2,2)- and β(2,2,3)-amino esters and derivatives containing an all-carbon quaternary center. Org Lett 2015; 17:322-5. [PMID: 25551418 DOI: 10.1021/ol503432b] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
β-Amino acids are routinely incorporated into peptidic drugs to increase their stability and to incur conformational biases. However, the synthesis of highly substituted β-amino acids still represents a great challenge. A new approach to their preparation is reported involving a Vilsmeier-Haack reaction with nonaromatic carbon nucleophiles. The highly challenging preparation of contiguous tertiary and all-carbon quaternary centers was successfully used to generate several β(2,2,3)-amino esters, such as derivatives of homoproline, homoalanine, and homopipecolinic esters.
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Affiliation(s)
- Alexandre Romanens
- Département de Chimie, Université de Sherbrooke , 2500 boulevard de l'Université, Sherbrooke, Québec J1K 2R1, Canada
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13
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Kiss L, Kardos M, Forró E, Fülöp F. Stereocontrolled One-Step Synthesis of Difunctionalised Cispentacin Derivatives through Ring-Opening Metathesis of Norbornene β-Amino Acids. European J Org Chem 2015. [DOI: 10.1002/ejoc.201403493] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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14
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Davies SG, Fletcher AM, Thomson JE. Direct asymmetric syntheses of chiral aldehydes and ketones via N-acyl chiral auxiliary derivatives including chiral Weinreb amide equivalents. Chem Commun (Camb) 2014; 49:8586-98. [PMID: 23959006 DOI: 10.1039/c3cc45463k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This article covers N-acyl chiral auxiliary-based approaches to the asymmetric synthesis of enantiopure aldehydes and ketones. The use of diastereoisomerically pure N-acyl derivatives of chiral auxiliaries (including chiral Weinreb amide equivalents) and their conversion to the corresponding enantiopure aldehydes and ketones in a single synthetic operation by treatment with a hydride reducing agent or an organometallic reagent, respectively, are highlighted.
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Affiliation(s)
- Stephen G Davies
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK.
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15
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Wu L, Xie C, Mei H, Soloshonok VA, Han J, Pan Y. Highly efficient and generalized asymmetric synthesis of quaternary stereogenic carbon-containing β-amino indanones/indanoles via Mannich-type additions between 1-indanones and N-tert-butanesulfinylketimines. Org Biomol Chem 2014; 12:4620-7. [DOI: 10.1039/c4ob00489b] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1-Indanone and acetophenone derived enolates undergo Mannich-type reactions with ketimines in up to 98% yields and >99 : 1 diastereoselectivities.
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Affiliation(s)
- Lingmin Wu
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing, China
| | - Chen Xie
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing, China
| | - Haibo Mei
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing, China
| | - Vadim A. Soloshonok
- Department of Organic Chemistry I
- Faculty of Chemistry
- University of the Basque Country UPV/EHU
- 20018 San Sebastian, Spain
- IKERBASQUE
| | - Jianlin Han
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing, China
- Institute for Chemistry & BioMedical Sciences
- Nanjing University
| | - Yi Pan
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing, China
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16
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Cherepanova M, Kiss L, Forró E, Fülöp F. A De Novo Stereocontrolled Approach tosyn- andanti-Disubstituted Acyclic β2,3-Amino Acid Enantiomers. European J Org Chem 2013. [DOI: 10.1002/ejoc.201301281] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Abrunhosa-Thomas I, Plas A, Kandepedu N, Chalard P, Troin Y. Efficient synthesis of β'-amino-α,β-unsaturated ketones. Beilstein J Org Chem 2013; 9:486-95. [PMID: 23504648 PMCID: PMC3596044 DOI: 10.3762/bjoc.9.52] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 02/01/2013] [Indexed: 11/23/2022] Open
Abstract
A general and simple procedure to access chiral β'-amino-α,β-enones, in seven steps, from an α,β unsaturated ester has been described. The use of a Horner-Wadsworth-Emmons reaction as a key step for generating the β'-amino-α,β-enones, permits access to a range of substrates under mild conditions and in moderate to high yield.
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Affiliation(s)
- Isabelle Abrunhosa-Thomas
- Clermont Université, ENSCCF, Institut de Chimie de Clermont-Ferrand (ICCF), BP 10448, F-63000 Clermont-Ferrand, France ; CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand (ICCF), BP 80026, F-63171 Aubière, France
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18
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Bian J, Blakemore D, Warmus JS, Sun J, Corbett M, Rose CR, Bechle BM. Diastereoselective Synthesis of β-Heteroaryl syn-α-Methyl-β-Amino Acid Derivatives via a Double Chiral Auxiliary Approach. Org Lett 2013; 15:562-5. [DOI: 10.1021/ol3033785] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jianwei Bian
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
| | - David Blakemore
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
| | - Joseph S. Warmus
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
| | - Jianmin Sun
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
| | - Matthew Corbett
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
| | - Colin R. Rose
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
| | - Bruce M. Bechle
- Neusentis Chemistry, Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States, and The Portway Building, Granta Park, Cambridge, CB21 6GS, U.K
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19
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Herndon JW. The chemistry of the carbon–transition metal double and triple bond: Annual survey covering the year 2010. Coord Chem Rev 2012. [DOI: 10.1016/j.ccr.2012.02.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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20
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Edupuganti R, Davis FA. Synthesis and applications of masked oxo-sulfinamides in asymmetric synthesis. Org Biomol Chem 2012; 10:5021-31. [PMID: 22576951 DOI: 10.1039/c2ob25345c] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This short perspective reports on the synthesis and applications of a class of chiral amino carbonyl compounds, masked oxo-sulfinamides where the amine is protected with an N-sulfinyl moiety and the carbonyl group is protected as the ketal or 1,3-dithiane. These polyfunctionalized chiral building blocks are prepared by addition of organometallic reagents to masked oxo-sulfinimines (N-sulfinyl imines) or the addition of oxo-organometallic reagents and lithio-1,3-dithianes to sulfinimines. Because unmasking of the amino and carbonyl groups results in cyclic imines, these chiral building blocks are particularly useful for the asymmetric synthesis of functionalized nitrogen heterocycles, including prolines, pipecolic acids, pyrrolidines, homotropinones, tropinones, and tropane alkaloids such as cocaine and C-1 cocaine analogues.
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21
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Yu CB, Gao K, Chen QA, Chen MW, Zhou YG. Enantioselective Pd-catalyzed hydrogenation of tetrasubstituted olefins of cyclic β-(arylsulfonamido)acrylates. Tetrahedron Lett 2012. [DOI: 10.1016/j.tetlet.2012.03.035] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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22
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Lin P, Song B, Bhadury PS, Hu D, Zhang Y, Jin L, Yang S. Chiral Cinchona Alkaloid-Thiourea Catalyzed Mannich Reaction for Enantioselective Synthesis of β-Amino Ketones Bearing Benzothiazol Moiety. CHINESE J CHEM 2011. [DOI: 10.1002/cjoc.201180413] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Davis FA, Xu P. Asymmetric synthesis of anti-α-substituted β-amino ketones from sulfinimines. J Org Chem 2011; 76:3329-37. [PMID: 21417438 DOI: 10.1021/jo2002352] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Previously unknown, enantiopure, β-amino ketones were prepared in modest yield by addition of lithium reagents to N-sulfinyl anti-α-substituted β-amino Weinreb amides. Grignard reagents failed to add to these Weinreb amides in contrast to the syn-α-substituted isomers which did. The anti-α-substituted β-amino Weinreb amides were prepared by addition of LiN(OMe)Me to the corresponding N-sulfinyl anti-α-substituted β-amino esters because α-alkylation of N-sulfinyl β-amino Weinreb amide enolates resulted in poor diastereoselectivities.
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Affiliation(s)
- Franklin A Davis
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA.
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24
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Blangetti M, Croce G, Deagostino A, Mussano E, Prandi C, Venturello P. Asymmetric Synthesis of Ethoxydienamines in Superbasic Medium Mediated by Chiral Sulfinyl Group. J Org Chem 2011; 76:1814-20. [DOI: 10.1021/jo1024943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Gianluca Croce
- Dipartimento di Scienze e Tecnologie Avanzate, Università degli Studi del Piemonte Orientale “Amedeo Avogadro”, Viale Teresa Michel, 11-15121 Alessandria, Italy
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25
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Ueda M, Matsubara H, Yoshida KI, Sato A, Naito T, Miyata O. Regiodivergent Addition of Carbon Units to Dual-Activated Alkynes for Stereoselective Construction of Tetrasubstituted Alkenes. Chemistry 2011; 17:1789-92. [DOI: 10.1002/chem.201002744] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Indexed: 11/06/2022]
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26
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An expedient conversion of α-amino acids into Weinreb amides using COMU® as a coupling agent. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2010.10.169] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Barrios FJ, Zhang X, Colby DA. Dialkylaluminum N,O-Dimethylhydroxylamine Complex as a Reagent to Mask Reactive Carbonyl Groups in Situ from Nucleophiles. Org Lett 2010; 12:5588-91. [PMID: 21038923 DOI: 10.1021/ol102495v] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Francis J. Barrios
- Department of Chemistry and Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
| | - Xuechao Zhang
- Department of Chemistry and Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
| | - David A. Colby
- Department of Chemistry and Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
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