Asymmetric Morita–Baylis–Hillman reactions of 2-cyclohexen-1-one catalyzed by chiral biaryl-based bis(thiourea) organocatalysts
摘要:
Newly-developed bis(thiourea) 1d was found to be an efficient organocatalyst for the Morita-Baylis-Hillman reaction. High enantioselectivities were obtained in the reaction of 2-cyclohexen-1-one with both aromatic aldehydes (up to 84% ee) and aliphatic aldehydes (up to 96% ee). (C) 2011 Elsevier Ltd. All rights reserved.
Asymmetric Morita−Baylis−Hillman Reactions Catalyzed by Chiral Brønsted Acids
作者:Nolan T. McDougal、Scott E. Schaus
DOI:10.1021/ja037705w
日期:2003.10.1
Chiral BINOL-derived Brønstedacidscatalyze the enantioselective asymmetric Morita-Baylis-Hillman (MBH) reaction of cyclohexenone with aldehydes. The asymmetric MBH reaction requires 2-20 mol % of the chiral Brønstedacid 2e or 2f and triethylphosphine as the nucleophilic promoter. The reaction products are obtained in good yields (39-88%) and high enantioselectivities (67-96% ee). The Brønsted-acid-catalyzed
A new chiral bis-thiourea-type organocatalyst 2 developed for the Baylis–Hillmanreaction provided a drastic rate enhancement. Allylic alcohols were obtained with up to 90% ee in the case of cyclohexanecarboxaldehyde (4i).
The Development of the Asymmetric Morita—Baylis—Hillman Reaction Catalyzed by Chiral Brønsted Acids
作者:Nolan T. McDougal、Whitney L. Trevellini、Stacy A. Rodgen、Laura T. Kliman、Scott E. Schaus
DOI:10.1002/adsc.200404122
日期:2004.8
development of a chiral Brønsted acid-catalyzed asymmetric Morita–BaylisHillman (MBH) reaction of cyclohexenone with aldehydes. During the course of our studies on chiral Lewis acid-promoted MBH reactions, we discovered that chiral binaphthol-derived Brønsted acids serve as promoters of the asymmetric MBH reaction. We propose that the phosphonium enolate of cyclohexenone is stabilized via hydrogen-bonding
Asymmetric Morita-Baylis-Hillman Reaction Catalyzed by Simple Amino Alcohol Derived Thioureas
作者:Alessandra Lattanzi
DOI:10.1055/s-2007-984882
日期:——
Thioureas straightforwardly derived from commercially available enantiopure amino alcohols have been found to promote the asymmetric Morita-Baylis-Hillman reaction of 2-cyclohexen-1-one and different aldehydes in the presence of triethylamine under solvent-free conditions. The corresponding allylic alcohols were obtained in good to high yields and up to 88% ee.
作者:Jian Wang、Hao Li、Xinhong Yu、Liansuo Zu、Wei Wang
DOI:10.1021/ol051822+
日期:2005.9.1
[reaction: see text] A new bifunctional binaphthyl-derived amine thiourea organocatalyst has been developed to promote enantioselective Morita-Baylis-Hillman reaction of cyclohexenone with a wide range of aldehydes. The process, catalyzed by the amine thiourea, affords synthetically valuable chiralallylic alcohol building blocks in high yields and high enantioselectivities.