Ambient Synthesis of Dienals via Triazole–Gold and Amine Catalysis Relay
作者:Stephen E. Motika、Qiaoyi Wang、Xiaohan Ye、Xiaodong Shi
DOI:10.1021/ol503393a
日期:2015.1.16
A highly efficient synthesis of substituted conjugated dienals was developed through a triazole–gold (TA–Au)-catalyzed propargyl vinyl etherrearrangement followed by an amine catalyzed allene–aldehyde tautomerization. Various substituted vinylogous aldehydes were prepared in one pot with good to excellent yields (up to 95%) under mild conditions with high atom economy.
Rh(I)-Catalyzed Transformation of Propargyl Vinyl Ethers into (<i>E</i>,<i>Z</i>)-Dienals: Stereoelectronic Role of <i>trans</i> Effect in a Metal-Mediated Pericyclic Process and a Shift from Homogeneous to Heterogeneous Catalysis During a One-Pot Reaction
作者:Dinesh V. Vidhani、Marie E. Krafft、Igor V. Alabugin
DOI:10.1021/jo402505f
日期:2014.1.3
experiments and computations reveals unusual features of stereoselective Rh(I)-catalyzed transformation of propargyl vinylethers into (E,Z)-dienals. The first step, the conversion of propargyl vinylethers into allene aldehydes, proceeds under homogeneous conditions via a “cyclization-mediated” mechanism initiated by Rh(I) coordination at the alkyne. This path agrees well with the small experimental