1190072-01-5Relevant articles and documents
Enantioselective reduction of α,β-enones using an oxazaborolidine catalyst generated in situ from a chiral lactam alcohol
Kawanami, Yasuhiro,Mikami, Yudai,Kiguchi, Kazuya,Harauchi, Yuki,Yanagita, Ryo C.
, p. 1891 - 1894 (2011)
The oxazaborolidine catalyst prepared in situ from the chiral lactam alcohol 3 and 4-iodophenoxyborane was found to catalyze the enantioselective reduction of α,β-enones at -40 °C with a high level of enantioselectivity of up to 90% ee.
Backbone-Modified C2-Symmetrical Chiral Bisphosphine TMS-QuinoxP*: Asymmetric Borylation of Racemic Allyl Electrophiles
Imamoto, Tsuneo,Ito, Hajime,Iwamoto, Hiroaki,Ozawa, Yu,Takenouchi, Yuta
supporting information, p. 6413 - 6422 (2021/05/31)
A new C2-symmetrical P-chirogenic bisphosphine ligand with silyl substituents on the ligand backbone, (R,R)-5,8-TMS-QuinoxP*, has been developed. This ligand showed higher reactivity and enantioselectivity for the direct enantioconvergent borylation of cy
Enantioselective NiH/Pmrox-Catalyzed 1,2-Reduction of α,β-Unsaturated Ketones
Chen, Fenglin,Zhang, Yao,Yu, Lei,Zhu, Shaolin
, p. 2022 - 2025 (2017/02/15)
The enantioselective 1,2-reduction of α,β-unsaturated ketones was achieved using a NiH catalyst in the presence of pinacolborane. This mild process represents a general method to access a wide variety of structurally diverse α-chiral allylic alcohols in excellent yields and enantioselectivity, as well as very high levels of ambidoselectivity for 1,2- over 1,4-reduction. Furthermore, for reactions on a 10 mmol scale, catalyst loadings as low as 0.5 mol % could be employed to deliver product without any detrimental effect on the yield, enantio-, or ambidoselectivity.
Kinetic resolution of secondary alcohols using amidine-based catalysts
Li, Ximin,Jiang, Hui,Uffman, Eric W.,Guo, Lei,Zhang, Yuhua,Yang, Xing,Birman, Vladimir B.
experimental part, p. 1722 - 1737 (2012/04/04)
Kinetic resolution of racemic alcohols has been traditionally achieved via enzymatic enantioselective esterification and ester hydrolysis. However, there has long been considerable interest in devising nonenzymatic alternative methods for this transformation. Amidine-based catalysts (ABCs), a new class of enantioselective acyl transfer catalysts developed in our group, have demonstrated, inter alia, high efficacy in the kinetic resolution of benzylic, allylic, and propargylic secondary alcohols and 2-substituted cycloalkanols, and thus provide a viable alternative to enzymes.
Catalyst versus substrate induced selectivity: Kinetic resolution by palladacycle catalyzed allylic imidate rearrangements
Peters, Rene,Xin, Zhuo-Qun,Maier, Frank
, p. 1770 - 1774 (2011/03/23)
Making chairs: A kinetic resolution of allylic imidates by planar chiral palladacycles is described which is the result of high face selectivity for olefin coordination to the catalyst and inherent substrate selectivity. These studies confirm that planar chiral palladacycles mainly operate via (half)chair-like transition states/intermediates.
Enantioselective, organocatalytic reduction of ketones using bifunctional thiourea-amine catalysts
Li, De Run,He, Anyu,Falck
supporting information; experimental part, p. 1756 - 1759 (2010/10/04)
Prochiral ketones are reduced to enantioenriched, secondary alcohols using catecholborane and a family of air-stable, bifunctional thiourea-amine organocatalysts. Asymmetric induction is proposed to arise from the in situ complexation between the borane and chiral thiourea-amine organocatalyst resulting in a stereochemically biased boronate-amine complex. The hydride in the complex is endowed with enhanced nucleophilicity while the thiourea concomitantly embraces and activates the carbonyl.
Chiral thiourea compounds and process for enantioselective reduction of ketones
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Page/Page column 16-17, (2009/10/18)
Chiral thioureas are effective catalysts for the borane reduction of prochiral ketones to optically active alcohols. A prochiral ketone may be reduced to an optically active alcohol in the presence of a substantially sub-stoichiometric amount of chiral thiourea. The asymmetric thiourea compound of the present invention may be produced according to a production method described herein.
