The Ireland–Claisen rearrangement is a type of Claisen rearrangement. The mechanism is therefore a concerted [3,3]-sigmatropic rearrangement which according to the Woodward–Hoffmann rules show a concerted, suprafacial, pericyclic reaction pathway. The first reported Claisen rearrangement is the [3,3]-sigmatropic rearrangement of an allyl phenyl ether to intermediate 1, which quickly tautomerizes to a 2-allylphenol. Meta-substitution affects the regioselectivity of this rearrangement. For example, electron withdrawing groups (such as bromide) at the meta-position direct the …

Abnormal Claisen Rearrangement - Wiley Online Library

WebScheme 1 Examples of the acyclic diastereoselective Ireland–Claisen rearrangement forming adjacent chiral quaternary centers O O CO 2 H Ph N NLi CF 3 Me 3 SiCl, THF –78 to 25 °C 85%, dr 5:1 ... WebNov 21, 2003 · The E- and Z-silyl enol ethers 4 derived from allyl 3-R-3-dimethyl(phenyl)silylpropanoate (R = Me, Pr(i) and Ph) and the Z-silyl enol ethers 7 derived … chromium 2 electron configuration

The Claisen Rearrangement - University of Chicago

WebFor example, facile access to stereodefined ester enolates 3, 4 renders the Ireland-Claisen rearrangement 5, 6 extremely synthetically appealing, while the challenge entailed in the preparation of stereodefined allyl vinyl ethers 7 explains why the “simpler” aliphatic Claisen rearrangement 8 has traditionally received more modest attention. WebAug 27, 2024 · An Ireland–Claisen rearrangement of 6 afforded an intermediate silyl enol ether following the γ-deprotonation which, upon warming, led to carboxylic acid 7 as a single diastereoisomer (86% yield). The exclusive formation of the E -alkenylstannane in 7 provided a valuable extension of Claisen methodology for direct linkage with Stille cross ... WebClaisen-Ireland重排 简介 编辑 播报 烯酮硅烷基缩醛中间体的Claisen重排反应相类似的还有，烯酮锌（Reformatsky-Claisen重排）、甲酰基醋酸烯酮（Carroll重排）等方法也广为人知。 chromium 2 ion electron configuration