1193433-64-5Relevant academic research and scientific papers
Cooperative catalysis of metal and O-H...O/sp3-C-H...O two-point hydrogen bonds in alcoholic solvents: Cu-catalyzed enantioselective direct alkynylation of aldehydes with terminal alkynes
Ishii, Takaoki,Watanabe, Ryo,Moriya, Toshimitsu,Ohmiya, Hirohisa,Mori, Seiji,Sawamura, Masaya
, p. 13547 - 13553 (2013)
Catalyst-substrate hydrogen bonds in artificial catalysts usually occur in aprotic solvents, but not in protic solvents, in contrast to enzymatic catalysis. We report a case in which ligand-substrate hydrogen-bonding interactions cooperate with a transition-metal center in alcoholic solvents for enantioselective catalysis. Copper(I) complexes with prolinol-based hydroxy amino phosphane chiral ligands catalytically promoted the direct alkynylation of aldehydes with terminal alkynes in alcoholic solvents to afford nonracemic secondary propargylic alcohols with high enantioselectivities. Quantum-mechanical calculations of enantiodiscriminating transition states show the occurrence of a nonclassical sp3-C-H...O hydrogen bond as a secondary interaction between the ligand and substrate, which results in highly directional catalyst-substrate two-point hydrogen bonding. Efficient enantioselective direct carbonyl addition of terminal alkynes is achieved through ligand-substrate two-point hydrogen bonds consisting of O-H...O and sp3-C-H...O interactions that cooperate with copper in alcoholic solvents (see picture). Copyright
Enantioselective addition of organozinc reagents to carbonyl compounds catalyzed by a camphor derived chiral γ-amino thiol ligand
Wu, Hsyueh-Liang,Wu, Ping-Yu,Cheng, Ying-Ni,Uang, Biing-Jiun
, p. 2656 - 2665 (2016/05/10)
In this article, the design and synthesis of the chiral camphor derived γ-amino thiol ligand 17 and its application in catalytic enantioselective carbon-carbon forming reactions through the addition of organozinc reagents to carbonyl compounds is described. The catalytic activity and enantioselectivity of ligand 17 is demonstrated in the enantioselective addition of various organozinc reagents to aldehydes and ketoesters, offering the corresponding alcohols in high yields and enantioselectivities. The role of the mercapto group in the highly enantioselective 1,2-addition reaction of organozincs to aldehyde is also discussed.
METHOD FOR PREPARING PROPARGYLIC ALCOHOL CATALYZED BY 2-MORPHOLINOISOBORNANE-10-THIOL
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Page/Page column 7-9, (2011/12/13)
A method for preparing a propargylic alcohol catalyzed by 2-morpholinoisobornane-10-thiol (MITH) is disclosed, which includes reacting R1CHO with R2CCH in the presence of R3ZnR4 and MITH, wherein each of R1, R2, R3, and R4, independently, is optionally substituted alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkylsilyl, heterocycloalkyl, heterocycloalkenyl, aryl, aryloxy, or heteroaryl. The method can give enantioenriched propargylic alcohols with good enantioselective at low loading of MITH.
Asymmetric synthesis of propargylic alcohols catalyzed by (-)-MITH
Wu, Ping-Yu,Wu, Hsyueh-Liang,Shen, Ying-Ying,Uang, Biing-Jiun
experimental part, p. 1837 - 1841 (2010/01/06)
This investigation describes that in the presence of 2.5 mol % of (-)-2-exo-morpholinoisobornane-10-thiol (MITH) 1, catalytic asymmetric alkynylation of aldehydes gives enantioenriched propargylic alcohols with good enantioselectivities.
