Oxidative and Enantioselective Cross-Coupling of Aldehydes and Nitromethane Catalyzed by Diphenylprolinol Silyl Ether
作者:Yujiro Hayashi、Takahiko Itoh、Hayato Ishikawa
DOI:10.1002/anie.201006885
日期:2011.4.18
Synthetically important β‐substituted γ‐nitro aldehydes have been synthesized with excellent enantioselectivity by the cross‐coupling reaction of β‐aryl substituted aldehydes or γ,δ‐unsaturated aldehydes and nitromethane using 2,3‐dichloro‐5,6‐dicyanoquinone (DDQ) and diphenylprolinol silyl ether as an oxidant and catalyst, respectively (see scheme; TMS=trimethylsilyl).
Diphenylprolinol Silyl Ether as Catalyst of an Asymmetric, Catalytic, and Direct Michael Reaction of Nitroalkanes with α,β-Unsaturated Aldehydes
作者:Hiroaki Gotoh、Hayato Ishikawa、Yujiro Hayashi
DOI:10.1021/ol702545z
日期:2007.12.1
A catalyticenantioselective direct conjugate addition of nitroalkanes to alpha,beta-unsaturated aldehydes using diphenylprolinolsilylether as an organocatalyst has been developed. Using this methodology as a key step, short syntheses of therapeutically useful compounds have also been accomplished.
Reactivity and Selectivity of Iminium Organocatalysis Improved by a Protein Host
作者:Alexander R. Nödling、Katarzyna Świderek、Raquel Castillo、Jonathan W. Hall、Antonio Angelastro、Louis C. Morrill、Yi Jin、Yu-Hsuan Tsai、Vicent Moliner、Louis Y. P. Luk
DOI:10.1002/anie.201806850
日期:2018.9.17
There has been growing interest in performing organocatalysis within a supramolecular system as a means of controlling reaction reactivity and stereoselectivity. Here, a protein is used as a host for iminium catalysis. A pyrrolidine moiety is covalently linked to biotin and introduced to the proteinhost streptavidin for organocatalytic activity. Whereas in traditional systems stereoselectivity is
Stereochemical Control of Enzymatic Carbon-Carbon Bond-Forming Michael-Type Additions by “Substrate Engineering”
作者:Yufeng Miao、Pieter G. Tepper、Edzard M. Geertsema、Gerrit J. Poelarends
DOI:10.1002/ejoc.201601126
日期:2016.11
of acetaldehyde to β‐nitrostyrene derivatives to yield chiral γ‐nitroaldehydes, which are important precursors for pharmaceutically active γ‐aminobutyric acids. In this study, we investigated the effect of different substituents at the aromatic ring of the Michael acceptor on the catalytic efficiency and stereoselectivity of the 4‐OT‐catalyzed acetaldehyde addition reactions. Highly enantioenriched (R)‐