O,ω‐Unsaturated N‐tosyl alkoxyamines undergo unexpected RhIII‐catalyzed intramolecular cyclization by oxyamination to produce oxygen‐containing heterocycles. Mechanistic studies show that an aziridine intermediate seems to be responsible for the formation of the heterocycles, possibly via a RhV species.
Palladium-Catalyzed Alkene Carboalkoxylation Reactions of Phenols and Alcohols for the Synthesis of Carbocycles
作者:Derick R. White、Madeline I. Herman、John P. Wolfe
DOI:10.1021/acs.orglett.7b01975
日期:2017.8.18
triflate electrophile and exogenous alcohol or phenol nucleophiles are described. These transformations afford substituted indanyl or alkylidenecyclopentyl ethers in high yield with excellent diastereoselectivity. The transformations proceed through intermolecular capture of an intermediate [Pd(II)-alkene]+[OTf]− complex by the alcohol or phenol nucleophile.
Copper(I)-Catalyzed Borylative <i>exo</i>-Cyclization of Alkenyl Halides Containing Unactivated Double Bond
作者:Koji Kubota、Eiji Yamamoto、Hajime Ito
DOI:10.1021/ja3104582
日期:2013.2.20
A borylativeexo-cyclization of alkenylhalides has been reported. The reaction includes the regioselective addition of a borylcopper(I) intermediate to unactivated terminal alkenes, followed by the intramolecular substitution of the resulting alkylcopper(I) moiety for the halide leaving groups. Experimental and theoretical investigations of the reaction mechanism have also been described. This reaction
mCPBA-mediated dioxygenation of unactivated alkenes for the synthesis of 5-imino-2-tetrahydrofuranyl methanol derivatives
作者:Xiaojun Deng、Luwen Zhang、Huixia Liu、Yu Bai、Wei He
DOI:10.1016/j.tetlet.2020.152620
日期:2020.12
A mCPBA-mediated, metal-free, intramolecular dioxygenation reaction of unactivatedalkenes is reported. In the presence of m-chlorobenzoic peracid, different unsaturated amide substrates could be cyclized via epoxide intermediates, producing the corresponding 5-imino-2-tetrahydrofuranyl methanol products in up to 94% yield at room temperature.
Palladium-Catalyzed Trans-Selective Synthesis of Spirocyclic Cyclobutanes Using α,α-Dialkylcrotyl- and Allylhydrazones
作者:Isaiah K. Eckart-Frank、Sidney M. Wilkerson-Hill
DOI:10.1021/jacs.3c05699
日期:2023.8.23
vinylcyclobutanes in a diastereoselective fashion. We show 24 examples of a 1,1-insertion/4-exo-trig tandem process to produce these motifs. Additionally, spirocyclic alkylidene cyclobutanes can be obtained by using α,α-disubstituted allylated hydrazones (11 examples). In this study, we show that the aryl migrating group has a dramatic impact on the course of the reaction. Specifically, allylic C–H insertion