Hypervalent iodine initiated intramolecular alkene dimerisation: a stereodivergent entry to cyclobutanes
作者:Yuxiang Zhu、Ignacio Colomer、Timothy J. Donohoe
DOI:10.1039/c9cc04383g
日期:——
The emergence of newmethods for the stereoselectivesynthesis of strained carbocycles is a challenging but worthwhile endeavour. Cyclobutanes, in particular, have attracted the attention of both medicinal chemists and material scientists for their unique properties. Herein, we present a newmethod that allows access to highly functionalized cyclobutanes with complementary all-trans and trans–cis–trans
codimerizations of styrene with vinyl acetate and with methylvinyl ketone gave 50% codimer and 125% codimers respectively. When nitroethylene and n-butyl vinylether were used as the vinyl compound, no codimers were formed. The codimerization of styrene-d3 with ethylene was also carried out. The reaction mechanism involving the five-coordinate hydridopalladiumolefin intermediate was proposed and discussed in
Applications of consecutive radical addition–elimination reactions in synthesis
作者:Jack E. Baldwin、David R. Kelly
DOI:10.1039/c39850000682
日期:——
Alkyl radicals add to the tri-n-butylstannyl substituted terminus of several alkenes; elimination of the stannyl radical results in a preparatively useful, carbon–carbon bond forming reaction, under mild and neutral conditions.
Stereospecific Aminative Cyclizations Triggered by Intermolecular Aza‐Prilezhaev Alkene Aziridination
作者:Matthew J. S. Smith、Wenbin Tu、Craig M. Robertson、John F. Bower
DOI:10.1002/anie.202312797
日期:2023.11.27
acidic reaction conditions (TFA), deprotection of BocNR(OSO2R) reagents triggers intermolecular aminative cyclizations of alkenes equipped with pendant nucleophiles. The processes are predicated on a sequence of stereospecific intermolecular aza-Prilezhaev aziridination followed by stereospecific opening by the pendant nucleophile.
Simple alkenes react with PhSeOTf and NaN3 in MeCN to afford beta-phenylseleno azides as the result of a stereospecific trans addition. The regioselectivity of the process is determined by the structure of the alkene.