A steric tethering approach enables palladium-catalysed C–H activation of primary amino alcohols
作者:Jonas Calleja、Daniel Pla、Timothy W. Gorman、Victoriano Domingo、Benjamin Haffemayer、Matthew J. Gaunt
DOI:10.1038/nchem.2367
日期:2015.12
higher-order nitrogen-containing molecules, commonly found in biologically active compounds and pharmaceutical agents. New methods for the construction of complex amines remain a continuous challenge to synthetic chemists. Here, we outline a general palladium-catalysed strategy for the functionalization of aliphatic C–H bonds within amino alcohols, an important class of smallmolecule. Central to this strategy
Development and Analysis of a Pd(0)-Catalyzed Enantioselective 1,1-Diarylation of Acrylates Enabled by Chiral Anion Phase Transfer
作者:Eiji Yamamoto、Margaret J. Hilton、Manuel Orlandi、Vaneet Saini、F. Dean Toste、Matthew S. Sigman
DOI:10.1021/jacs.6b11367
日期:2016.12.14
Enantioselective 1,1-diarylation of terminal alkenes enabled by the combination of Pd catalysis with a chiralanionphasetransfer (CAPT) strategy is reported herein. The reaction of substituted benzyl acrylates with aryldiazonium salts and arylboronic acids gave the corresponding 3,3-diarylpropanoates in moderate to good yields with high enantioselectivies (up to 98:2 er). Substituents on the benzyl
A Selenourea-Thiourea Brønsted Acid Catalyst Facilitates Asymmetric Conjugate Additions of Amines to α,β-Unsaturated Esters
作者:Yingfu Lin、William J. Hirschi、Anuj Kunadia、Anirudra Paul、Ion Ghiviriga、Khalil A. Abboud、Rachael W. Karugu、Mathew J. Vetticatt、Jennifer S. Hirschi、Daniel Seidel
DOI:10.1021/jacs.9b12457
日期:2020.3.25
enantioselectivity via the conjugate addition of cyclic amines to unactivated α,β-unsaturated esters. A related strategy enables the kineticresolution of racemic cyclic 2-arylamines, using benzyl acrylate as the resolving agent. Reactions are facilitated by an unprecedented selenourea-thiourea organocatalyst. As elucidated by DFT calculations and 13C kinetic isotope effects studies, the rate-limiting and enantiodetermining
asymmetric cycloaddition, a nitrogen-nitrogen double bond has never been investigated in chiral phosphine catalysis. In this paper, we present phosphine-catalyzed asymmetric [3+2] cycloaddition of diazenes with Morita-Baylis-Hillman (MBH) carbonates to give chiral dihydropyrazoles in high yields with excellent enantioselectivities. Various MBH carbonates and diazenes worked well under the mild reaction conditions
Mechanistic Investigations of the Pd(0)-Catalyzed Enantioselective 1,1-Diarylation of Benzyl Acrylates
作者:Manuel Orlandi、Margaret J. Hilton、Eiji Yamamoto、F. Dean Toste、Matthew S. Sigman
DOI:10.1021/jacs.7b06917
日期:2017.9.13
A mechanistic study of the Pd-catalyzed enantioselective 1,1-diarylation of benzyl acrylates that is facilitated by a chiral anion phase transfer (CAPT) process is presented. Kinetic analysis, labeling, competition, and nonlinear effect experiments confirm the hypothesized general mechanism and reveal the role of the phosphate counterion in the CAPT catalysis. The phosphate was found to be involved