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.
A highly efficient kinetic resolution of Morita–Baylis–Hillman adducts achieved by N–Ar axially chiral Pd-complexes catalyzed asymmetric allylation
作者:Feijun Wang、Shengke Li、Mingliang Qu、Mei-Xin Zhao、Lian-Jun Liu、Min Shi
DOI:10.1039/c1cc15543a
日期:——
Palladium complexes with an axially chiral NâAr framework have been developed. These complexes showed high stereoselectivities in asymmetric allylic arylation to achieve the kinetic resolution of MoritaâBaylisâHillman adducts, affording up to 99% ee of (E)-allylation products and 92% ee of recovered MoritaâBaylisâHillman adducts.
Asymmetric Morita–Baylis–Hillman reactions of 2-cyclohexen-1-one catalyzed by chiral biaryl-based bis(thiourea) organocatalysts
作者:Yuki Nakayama、Takashi Gotanda、Katsuji Ito
DOI:10.1016/j.tetlet.2011.09.064
日期:2011.11
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.