Lewis Acid-Catalyzed Tandem Diels−Alder Reaction/Retro-Claisen Rearrangement as an Equivalent of the Inverse Electron Demand Hetero Diels−Alder Reaction
作者:Huw M. L. Davies、Xing Dai
DOI:10.1021/jo050821s
日期:2005.8.1
A highly stereoselective formal inverse electron demand hetero Diels−Alder reaction (HDA) occurs on reaction of 2-aryl-α,β-unsaturated aldehydes with cyclopentadiene. The major pathway for this transformation is shown to be a Lewisacid-catalyzed tandem Diels−Alder reaction/retro-Claisen rearrangement.
A practical total synthesis of plaunotol via highly Z-selective Wittig olefination of α-acetal ketones
作者:Keiko Tago、Masami Arai、Hiroshi Kogen
DOI:10.1039/b001977l
日期:——
Helicobacter pylori, a causative agent in gastric ulcers and gastric adenocarcinoma, for example. In our investigation of the practical synthesis of 1, we have developed an efficient method for stereoselectivesynthesis of trisubstitutedolefinsvia a Z-selective Wittigreaction. The olefination of readily available aliphatic α-acetal ketones with triphenylphosphonium salts in the presence of a potassium base