enantioselective proton migration from skipped enynes to allenes as an efficient approach in chiral allenesynthesis. With catalyst loading as low as 0.5 mol %, the reaction proceeds smoothly under mild conditions without the need for additional stoichiometric reagents or generation of waste. Novel chiral ligand L6 plays a critical role in furnishing high catalyst activity, promoting regioselective protonation
A Simple and Efficient Conversion of Tertiary Cyclopropanols to 2-Substituted Allyl Halides
作者:Yurii Yu. Kozyrkov、Oleg G. Kulinkovich
DOI:10.1055/s-2002-20461
日期:——
tertiary cyclopropanols are converted into 2-substituted allyl bromides in high yields under the action of magnesium bromide in diethyl ether. Magnesium chloride, aluminiumchloride and titanium tetrachloride also induce effectively the transformation of cyclopropyl sulphonates into the corresponding allyl chlorides.
Nickel-Catalyzed Asymmetric Intramolecular Reductive Heck Reaction of Unactivated Alkenes
作者:Feiyan Yang、Youxiang Jin、Chuan Wang
DOI:10.1021/acs.orglett.9b02577
日期:2019.9.6
An asymmetric Ni-catalyzed intramolecular reductiveHeckreaction of unactivated alkenes tethered to aryl bromides has been accomplished, providing a variety of benzene-fused cyclic compounds bearing a quaternary stereogenic center in good to excellent yields and high enantioselectivities. A mechanism has been proposed, which involves the enantiodetermining migratory insertion and the following protonation