Low-valent titanium-mediated cyclopropanation of vinylogous esters.

Organic letters

PubMedID: 15228280

Masalov N, Feng W, Cha JK. Low-valent titanium-mediated cyclopropanation of vinylogous esters. Org Lett. 2004;6(14):2365-8.
[reaction: see text] Inter- and intramolecular titanium-mediated cyclopropanation reactions of vinylogous esters are reported. Comparison between the Kulinkovich cyclopropanation of esters and vinylogous esters provides mechanistic insight regarding reaction variables such as reaction temperature, solvents, and a Lewis acid additive.