A copper(II)-catalyzed, sequential Michael–aldol reaction for the preparation of 1,2-dihydroquinolines
作者:Anna M. Wagner、Claire E. Knezevic、Jessica L. Wall、Victoria L. Sun、Joshua A. Buss、LeeAnn T. Allen、Anna G. Wenzel
DOI:10.1016/j.tetlet.2011.12.017
日期:2012.2
A copper(II)-catalyzed, sequential Michael addition-aldol condensation reaction of N-carboxybenzyl-protected aminobenzaldehyde with various α,β-unsaturated N-acyl pyrroles is described. Substrate scope was found to include both aryl and aliphatic N-acyl pyrroles as the Michael acceptors, and isolated product yields as high as 93% were observed. The use of acetonitrile as the reaction solvent proved
An Approach for Rapid Increase in Molecular Complexity: Atom Economic Routes to Fused Polycyclic Ring Systems
作者:Barry M. Trost、Veronika Ehmke
DOI:10.1021/ol5009872
日期:2014.5.16
developed. This process generates alkynyl-substituted cyclopentanes in high yields and diastereo- and enantioselectivities. These chiral precursors are employed for the atom economic assembly of fused polycyclic hydrocarbons with hydroindene, hydroazulene, and hydrocyclopentanaphthalene scaffolds by consecutive cycloaddition reactions.
Al and friends: Asymmetricconjugateaddition of Me3Al to β,β‐disubstituted α,β‐unsaturated ketones in the presence copper and L1 leads to a highly efficient construction of an all‐carbon‐substituted chiral quaternarycenter. This result is the first example of an asymmetricconjugateaddition of Me3Al to acyclic enones to give a chiral quaternary carbon center with excellent yield and enantioselectivity
A domino Friedel–Crafts/nitro‐Michael reaction between 4‐substituted indoles and nitroethene is presented. The reaction is catalyzed by BINOL‐derived phosphoric acid catalysts, and delivers the corresponding 3,4‐ring‐fused indoles with very good results in terms of yields and diastereo‐ and enantioselectivities. The tricyclic benzo[cd]indole products bear a nitro group at the right position to serve
提出了 4-取代吲哚和硝基乙烯之间的多米诺弗里德尔-克拉夫茨/硝基-迈克尔反应。该反应由 BINOL 衍生的磷酸催化剂催化,并产生相应的 3,4-环稠合吲哚,在产率以及非对映和对映选择性方面具有非常好的结果。三环苯并[ cd ]吲哚产物在正确的位置带有硝基,可作为麦角生物碱的前体,如从一种加合物正式合成6,7-开麦角碱所证明的那样。DFT 计算表明,反应的结果源于关键硝酸中间体通过亲核加成途径的优先演化,而不是预期的通过质子化的“猝灭”。
Enantioselective Construction of Highly Substituted Vinylidenecylopentanes by Palladium-Catalyzed Asymmetric [3+2] Cycloaddition Reaction
作者:Barry M. Trost、Autumn Maruniak
DOI:10.1002/anie.201300275
日期:2013.6.10
A new cycloadduct: The title reaction of methylene‐trimethylenemethane (TMM) with α,β‐unsaturated N‐acyl pyrroles is an efficient method for the construction of vinylidenecyclopentanes. An asymmetric protocol using this unique donor forms cycloadducts in excellent yield and enantioselectivity, making use of a bisdiamidophosphite ligand derived from trans‐1,2‐stilbenediamine.