Highly Stereoselective Cobalt-Catalyzed Allylation of Functionalized Diarylzinc Reagents
作者:Paul Knochel、Guillaume Dunet
DOI:10.1055/s-2007-980344
日期:2007.6
Functionalized diarylzinc reagents react readily with allylic chlorides or phosphates in the presence of Co(acac)2 (10 mol%) to give the SN2 products in high yields and with retention of the double-bond configuration. Functionalities like ester, ketone, or cyano are tolerated.
the presence of gold nanoparticles supported on ZrO2 proceeded efficiently under mild reaction conditions to give the corresponding allyl sulfides in excellent yields. ZrO2-Supported gold nanoparticles showed excellent catalytic turnover and reusability. In addition, the C–O bonds of benzyl and propargyl phosphates underwent thioetherification to afford benzyl and propargyl sulfides. The reaction of
copper-catalyzed highly enantioselective umpolung allylic acylation reaction with acylsilanes as acyl anion equivalents. Triplet-quenching experiments and DFT calculations supported our reaction design, which is based on copper-to-acyl metal-to-ligand charge transfer (MLCT) photoexcitation that generates a charge-separated triplet state as a highly reactive intermediate. According to the calculations
We performed an organocatalyzed enantioselective kineticresolution (KR) of racemic diastereocontrolled secondaryalcohols bearing a quaternary stereocenter. This methodology is a general KR leading to the enantiocontrol of acyclic quaternary stereocenter with high levels of stereoselectivity (s up to 185) on a large scope. In addition, the hydroxyl function can easily serve as a traceless group by