1
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Saunthwal RK, Schwarz M, Mallick RK, Terry-Wright W, Clayden J. Enantioselective Intramolecular α-Arylation of Benzylamine Derivatives: Synthesis of a Precursor to Levocetirizine. Angew Chem Int Ed Engl 2023; 62:e202216758. [PMID: 36698284 DOI: 10.1002/anie.202216758] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/27/2023]
Abstract
A practical, transition metal-free method allows the enantioselective synthesis of α,α-diarylmethylamines by asymmetric α-arylation of benzylamines. Enantioselective lithiation of N'-aryl-N-benzyl-N-isopropyl ureas using a chiral lithium amide base generates a benzyllithium that undergoes an unactivated stereospecific intramolecular nucleophilic aromatic substitution to generate an α,α-diarylmethylamine in the form of its urea derivative, in up to >99 % ee. Treatment with acid induces an "azatropic shift" with retention of configuration, the product of which may be hydrolysed to the target amine.
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Affiliation(s)
- Rakesh K Saunthwal
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Maria Schwarz
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Rajendra K Mallick
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - William Terry-Wright
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Jonathan Clayden
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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2
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Man N, Li Y, Jie J, Li H, Yang H, Zhao Y, Fu H. Synthesis of Chiral Propargylamines, Chiral 1,2-Dihydronaphtho[2,1-b]furans and Naphtho[2,1-b]furans with C-Alkynyl N,N'-di-(tert-butoxycarbonyl)-aminals and β-Naphthols. Chemistry 2021; 27:12884-12889. [PMID: 34133047 DOI: 10.1002/chem.202102040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Indexed: 12/21/2022]
Abstract
Chiral phosphoric acid-catalyzed couplings of C-alkynyl N,N'-di-(tert-butoxycarbonyl)-aminals with β-naphthols led to chiral propargylamines in moderate to high yields with high to excellent enantioselectivity, in which the reactions underwent sequential chiral phosphoric acid-catalyzed in situ formation of N-(tert-butoxycarbonyl)-imines (N-Boc-imines) from the aminals, and 1,2-addition of β-naphthols to the N-Boc-imines. Chiral 1,2-dihydronaphtho[2,1-b]furans and naphtho[2,1-b]furans were prepared with satisfactory results when 10 mol% AgOAc and 20 mol% 2,6-lutidine or 1.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) were added to the resulting chiral propargylamines solution, respectively.
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Affiliation(s)
- Ningning Man
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yuming Li
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Jiyang Jie
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hongyun Li
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Haijun Yang
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yufen Zhao
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hua Fu
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
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3
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Peng H, Zhang Y, Zhu Y, Deng G. Silver(I)-Catalyzed Domino Cyclization/Cyclopropanation/Ring-Cleavage/Nucleophilic Substitution Reaction of Enynones with Enamines: Synthesis of 4-(Furan-2-yl)-3,4-dihydro-2H-pyrrol-2-one. J Org Chem 2020; 85:13290-13297. [DOI: 10.1021/acs.joc.0c01711] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Haiyun Peng
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081, China
- Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Hunan Normal University, Changsha 410081, China
| | - Yu Zhang
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081, China
- Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Hunan Normal University, Changsha 410081, China
| | - Yang Zhu
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081, China
- Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Hunan Normal University, Changsha 410081, China
| | - Guisheng Deng
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081, China
- Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Hunan Normal University, Changsha 410081, China
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4
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Asymmetric Organocatalytic C-C Bond Forming Reactions with Organoboron Compounds: A Mechanistic Survey. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900029] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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5
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Huang G, Huang W, Guo J, Xu D, Qu X, Zhai P, Zheng X, Weng J, Lu G. Enantioselective Synthesis of Triarylmethanes
via
Organocatalytic 1,6‐Addition of Arylboronic Acids to
para
‐Quinone Methides. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201801446] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Gong‐Bin Huang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Wei‐Hua Huang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Jing Guo
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Dong‐Liang Xu
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Xiao‐Chen Qu
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Pei‐Hong Zhai
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Xiu‐Hua Zheng
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Jiang Weng
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
| | - Gui Lu
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical SciencesSun Yat-sen University Guangzhou 510006 People's Republic of China
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6
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Jiang Y, Thomson RJ, Schaus SE. Asymmetric Traceless Petasis Borono-Mannich Reactions of Enals: Reductive Transposition of Allylic Diazenes. Angew Chem Int Ed Engl 2017; 56:16631-16635. [PMID: 29110383 PMCID: PMC5739942 DOI: 10.1002/anie.201708784] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/27/2017] [Indexed: 12/22/2022]
Abstract
The traceless Petasis borono-Mannich reaction of enals, sulfonylhydrazines, and allylboronates, catalyzed by chiral biphenols, results in an asymmetric reductive transposition of the in situ generated allylic diazene. Acyclic 1,4-diene products bearing either alkyl- or aryl-substituted benzylic stereocenters are afforded in excellent yields and enantiomeric ratios of up to 99:1. The use of crotylboronates in the reaction results in concomitant formation of two stereocenters in either a 1,4-syn or anti relationship from the corresponding E- or Z-crotylboronate used in the reaction. The use of β-monosubstituted enals in the asymmetric traceless Petasis borono-Mannich reaction of crotylboronates installs tertiary methyl-bearing stereocenters in good yields and high enantioselectivities.
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Affiliation(s)
- Yao Jiang
- Department of Chemistry, Center for Molecular Discovery, Boston University, 24 Cummington Mall, Boston, MA, 02215, USA
| | - Regan J Thomson
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
| | - Scott E Schaus
- Department of Chemistry, Center for Molecular Discovery, Boston University, 24 Cummington Mall, Boston, MA, 02215, USA
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7
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Jiang Y, Thomson RJ, Schaus SE. Asymmetric Traceless Petasis Borono‐Mannich Reactions of Enals: Reductive Transposition of Allylic Diazenes. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201708784] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Yao Jiang
- Department of Chemistry, Center for Molecular Discovery Boston University 24 Cummington Mall Boston MA 02215 USA
| | - Regan J. Thomson
- Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
| | - Scott E. Schaus
- Department of Chemistry, Center for Molecular Discovery Boston University 24 Cummington Mall Boston MA 02215 USA
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8
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Syu JF, Lin HY, Cheng YY, Tsai YC, Ting YC, Kuo TS, Janmanchi D, Wu PY, Henschke JP, Wu HL. Design and Synthesis of Chiral Diene Ligands for RhI
-Catalyzed Enantioselective Arylation of N
-DPP-protected Aldimines: Synthesis of the Antifungal Agent Bifonazole. Chemistry 2017; 23:14515-14522. [DOI: 10.1002/chem.201702509] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Indexed: 02/07/2023]
Affiliation(s)
- Jin-Fong Syu
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Huang-Ying Lin
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Yu-Yi Cheng
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Yao-Chu Tsai
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Yi-Ching Ting
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Ting-Shen Kuo
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Damodar Janmanchi
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
| | - Ping-Yu Wu
- Oleader Technologies Co. Ltd.; 1F., No. 8, Aly. 29, Ln. 335, Chenggong Rd. Hukou Township, Hsinchu County 30345 Taiwan) (ROC
| | - Julian P. Henschke
- ScinoPharm Taiwan; No. 1 Nan-Ke Eighth Road, Tainan Science-Based Industrial Park Shan-Hua, Tainan County 74144 Taiwan) (ROC
| | - Hsyueh-Liang Wu
- Department of Chemistry; National Taiwan Normal University; No. 88 Section 4 Tingzhou Road, Taipei City 11677 Taiwan) (ROC
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9
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Kwon Y, Rhee YH, Park J. Chemoselective, Isomerization-Free Synthesis of N
-Acylketimines from N-H Imines. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201601406] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Yearang Kwon
- Department of Chemistry; POSTECH (Pohang University of Science and Technology); Pohang 37673 Korea
| | - Young Ho Rhee
- Department of Chemistry; POSTECH (Pohang University of Science and Technology); Pohang 37673 Korea
| | - Jaiwook Park
- Department of Chemistry; POSTECH (Pohang University of Science and Technology); Pohang 37673 Korea
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10
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Jiang Y, Schaus SE. Asymmetric Petasis Borono-Mannich Allylation Reactions Catalyzed by Chiral Biphenols. Angew Chem Int Ed Engl 2017; 56:1544-1548. [PMID: 28052567 PMCID: PMC5716625 DOI: 10.1002/anie.201611332] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Indexed: 12/25/2022]
Abstract
Chiral biphenols catalyze the asymmetric Petasis borono-Mannich allylation of aldehydes and amines through the use of a bench-stable allyldioxaborolane. The reaction proceeds via a two-step, one-pot process and requires 2-8 mole % of 3,3'-Ph2 -BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99 %) and high enantioselectivies (er up to 99:1). The catalytic reaction is a true multicomponent condensation reaction whereas both the aldehyde and the amine can possess a wide range of structural and electronic properties. Use of crotyldioxaborolane in the reaction results in stereodivergent products with anti- and syn-diastereomers both in good diastereoselectivities and enantioselectivities from the corresponding E- and Z-borolane stereoisomers.
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Affiliation(s)
- Yao Jiang
- Department of Chemistry, Center for Molecular Discovery, Boston University, 24 Cummington Mall, Boston, MA, 02215, USA
| | - Scott E Schaus
- Department of Chemistry, Center for Molecular Discovery, Boston University, 24 Cummington Mall, Boston, MA, 02215, USA
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11
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Jiang Y, Schaus SE. Asymmetric Petasis Borono-Mannich Allylation Reactions Catalyzed by Chiral Biphenols. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611332] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yao Jiang
- Department of Chemistry, Center for Molecular Discovery; Boston University; 24 Cummington Mall Boston MA 02215 USA
| | - Scott E. Schaus
- Department of Chemistry, Center for Molecular Discovery; Boston University; 24 Cummington Mall Boston MA 02215 USA
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12
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Xiao X, Zhang W, Lu X, Deng Y, Jiang H, Zeng W. Copper-Catalyzed Addition of Alkylboranes to Iminoacetates: Access to α-Alkyl Branched α-Amino Acids. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Xinsheng Xiao
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering; South China University of Technology; Guangzhou 510641 People's Republic of China
| | - Wei Zhang
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering; South China University of Technology; Guangzhou 510641 People's Republic of China
| | - Xiaoxia Lu
- Chengdu Institute of Biology; Chinese Academy of Sciences; Chengdu 610041 People's Republic of China
| | - Yuanfu Deng
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering; South China University of Technology; Guangzhou 510641 People's Republic of China
| | - Huangfeng Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering; South China University of Technology; Guangzhou 510641 People's Republic of China
| | - Wei Zeng
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering; South China University of Technology; Guangzhou 510641 People's Republic of China
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13
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Lapuerta I, Vera S, Oiarbide M, Palomo C. Development of a syn-Selective Mannich Reaction of Aldehydes with Propargylic Imines by Dual Catalysis: Asymmetric Synthesis of Functionalized Propargylic Amines. Chemistry 2016; 22:7229-37. [DOI: 10.1002/chem.201600635] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Irati Lapuerta
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Silvia Vera
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Mikel Oiarbide
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Claudio Palomo
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
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14
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Stefani HA, Manarin F, Khan AN, Vasconcelos SNS. Ytterbium(III)-Catalyzed Addition Reaction of Alkynyltrifluoroborate Salts to α-Imino Esters: Efficient Synthesis of β-Unsaturated α-Amino Esters. European J Org Chem 2013. [DOI: 10.1002/ejoc.201301421] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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15
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Kano T, Yurino T, Maruoka K. Organocatalytic Asymmetric Synthesis of Propargylamines with Two Adjacent Stereocenters: Mannich-Type Reactions of In Situ Generated C-Alkynyl Imines with β-Keto Esters. Angew Chem Int Ed Engl 2013; 52:11509-12. [DOI: 10.1002/anie.201304963] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 07/31/2013] [Indexed: 11/08/2022]
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16
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Kano T, Yurino T, Maruoka K. Organocatalytic Asymmetric Synthesis of Propargylamines with Two Adjacent Stereocenters: Mannich-Type Reactions of In Situ Generated C-Alkynyl Imines with β-Keto Esters. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201304963] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Schenker S, Zamfir A, Freund M, Tsogoeva SB. Developments in Chiral Binaphthyl‐Derived Brønsted/Lewis Acids and Hydrogen‐Bond‐Donor Organocatalysis. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001538] [Citation(s) in RCA: 160] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sebastian Schenker
- Department of Chemistry and Pharmacy Chair of Organic Chemistry I University of Erlangen‐Nuremberg Henkestrasse 42, 91054 Erlangen, Germany, Fax: +49‐9131‐85‐26865
| | - Alexandru Zamfir
- Department of Chemistry and Pharmacy Chair of Organic Chemistry I University of Erlangen‐Nuremberg Henkestrasse 42, 91054 Erlangen, Germany, Fax: +49‐9131‐85‐26865
| | - Matthias Freund
- Department of Chemistry and Pharmacy Chair of Organic Chemistry I University of Erlangen‐Nuremberg Henkestrasse 42, 91054 Erlangen, Germany, Fax: +49‐9131‐85‐26865
| | - Svetlana B. Tsogoeva
- Department of Chemistry and Pharmacy Chair of Organic Chemistry I University of Erlangen‐Nuremberg Henkestrasse 42, 91054 Erlangen, Germany, Fax: +49‐9131‐85‐26865
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Moquist PN, Kodama T, Schaus SE. Enantioselective addition of boronates to chromene acetals catalyzed by a chiral Brønsted acid/Lewis acid system. Angew Chem Int Ed Engl 2010; 49:7096-100. [PMID: 20721997 PMCID: PMC3035997 DOI: 10.1002/anie.201003469] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chiral α,β-dihydroxy carboxylic acids catalyze the enantioselective addition of alkenyl- and aryl boronates to chromene acetals. The optimal carboxylic acid is a tartaric acid amide, easily synthesized via a 3-step procedure. The reaction is enhanced by the addition of Lanthanide triflate salts such as cerium(IV)-and ytterbium(III) triflate. The chiral Brønsted acid and metal Lewis acid may be used in as low as 5 mol % relative to acetal substrate. Optimization of the reaction conditions can lead to yields >70% and enantiomeric ratios as high as 99:1. Spectroscopic and kinetic mechanistic studies demonstrate an exchange process leading to a reactive dioxoborolane intermediate leading to enantioselective addition to the pyrylium generated from the chromene acetal.
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Affiliation(s)
- Philip N. Moquist
- Department of Chemistry, Center for Chemical Methodology and Library Development at Boston University (CMLD-BU), Life Science and Engineering Building, Boston University, 24 Cummington Street, Boston, Massachusetts, 02215 (USA)
| | - Tomohiro Kodama
- Department of Chemistry, Center for Chemical Methodology and Library Development at Boston University (CMLD-BU), Life Science and Engineering Building, Boston University, 24 Cummington Street, Boston, Massachusetts, 02215 (USA)
| | - Scott E. Schaus
- Department of Chemistry, Center for Chemical Methodology and Library Development at Boston University (CMLD-BU), Life Science and Engineering Building, Boston University, 24 Cummington Street, Boston, Massachusetts, 02215 (USA)
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19
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Enantioselective Addition of Boronates to Chromene Acetals Catalyzed by a Chiral Brønsted Acid/Lewis Acid System. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201003469] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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20
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Hashimoto T, Kimura H, Maruoka K. Enantioselective Formal Alkenylations of Imines Catalyzed by Axially Chiral Dicarboxylic Acid Using Vinylogous Aza-Enamines. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201003600] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Hashimoto T, Kimura H, Maruoka K. Enantioselective Formal Alkenylations of Imines Catalyzed by Axially Chiral Dicarboxylic Acid Using Vinylogous Aza-Enamines. Angew Chem Int Ed Engl 2010; 49:6844-7. [DOI: 10.1002/anie.201003600] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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