Fluorinative Rearrangements of Substituted Phenylallenes Mediated by (Difluoroiodo)toluene: Synthesis of α-(Difluoromethyl)styrenes
作者:Zhensheng Zhao、Léanne Racicot、Graham K. Murphy
DOI:10.1002/anie.201706798
日期:2017.9.11
(difluoroiodo)toluene in the presence of 20 mol % BF3⋅OEt2 to yield α‐difluoromethyl styrenes. This unprecedented reaction was entirely chemoselective for the internal allene π bond, and showed remarkable regioselectivity during the fluorination event. Substituted phenylallenes, phenylallenes possessing both phenyl‐ and α‐allenyl substituents, and diphenylallenes were investigated, and good functional‐group
Chlorination of phenylallene derivatives with 1-chloro-1,2-benziodoxol-3-one: synthesis of <i>vicinal</i>-dichlorides and chlorodienes
作者:Zhensheng Zhao、Graham K Murphy
DOI:10.3762/bjoc.14.67
日期:——
Allyl and vinyl chlorides represent important structural motifs in organic chemistry. Herein is described the chemoselective and regioselective reaction of aryl- and α-substituted phenylallenes with the hypervalent iodine (HVI) reagent 1-chloro-1,2-benziodoxol-3-one. The reaction typically results in vicinal dichlorides, except with proton-containing α-alkyl substituents, which instead give chlorinated
A convenient access to allylic triflones with allenes and triflyl chloride in the presence of (EtO)<sub>2</sub>P(O)H
作者:Jixiang Ni、Yong Jiang、Zhenyu An、Jingfeng Lan、Rulong Yan
DOI:10.1039/c9cc03096d
日期:——
A simple method for the preparation of allylic triflones from allenes and triflyl chloride in the presence of (EtO)2P(O)H has been developed. The features of this reaction are catalyst-free and simple starting substrates. This method tolerates diverse functional groups and substituted allylic triflones are obtained in moderate to good yields.
An Efficient Method for the Synthesis of Alkylidenecyclobutanones by Gold-Catalyzed Oxidative Ring Enlargement of Vinylidenecyclopropanes
作者:Wei Yuan、Xiang Dong、Yin Wei、Min Shi
DOI:10.1002/chem.201201161
日期:2012.8.20
Rings of gold: Vinylidenecyclopropanes can undergo efficientoxidativeringenlargements under mild conditions to give the corresponding alkylidenecyclobutanone derivatives in good yields (see scheme). A plausible mechanism for this transformation has been proposed, and a new AuI–N complex, which can be used as an efficient catalyst in this oxidation reaction, has been isolated.
金戒指:亚乙烯基环丙烷在温和的条件下可以进行有效的氧化环扩环,从而以高收率得到相应的亚烷基环丁酮衍生物(参见方案)。已经提出了这种转化的合理机制,并且已经分离出可以用作该氧化反应的有效催化剂的新的Au I – N络合物。
A Catalytic Method for the Preparation of Polysubstituted Cyclopentanes: [3+2] Cycloaddition of Vinylidenecyclopropanes with Activated Olefins Catalyzed by Triflic Imide
作者:Wei Li、Min Shi
DOI:10.1021/jo802294s
日期:2009.1.16
[3+2] Cycloadditions of vinylidenecyclopropanes (VDCPs) with electron-deficient olefins, such as methyl vinyl ketone (MVK) and acrylaldehyde, proceed smoothly in the presence of a catalytic amount of triflic imide (Tf2NH) to give the corresponding functionalized cyclopentanes in good to high yields.