Treatment of diazoalkanes with unsaturated compounds. No. 5. Catalytic cyclopropanation of unsaturated hydrocarbons with diazoethane

Autor: Tomilov, Yu. V., Bordakov, V. G., Lutsenko, A. I., Kozhinskii, S. O., Dolgii, I. E., Nefedov, O. M.
Zdroj: Russian Chemical Bulletin; June 1987, Vol. 36 Issue: 6 p1234-1239, 6p
Abstrakt: The preparative catalytic cyclopropanation of unsaturated hydrocarbons with diazoethane has been achieved for the first time. Addition of the ethylidene fragment to the C=C double bond occurs in a nonstereoselective manner and leads to the formation of the corresponding methylcyclopropanes in 55–70% total yields. In the presence of CuCl, all double bonds of unsaturated hydrocarbons are cyclopropanated with equal facility, whereas in the presence of (PhCN)2PdCl2, preferential regioselective cyclopropanation of strained endocyclic and terminal double bonds is observed, just as was true in the case of reactions with diazomethane.
Databáze: Supplemental Index