Thioacetals are selectively transformed into two types of terminal olefins, one with one-carbon homologation and the other with two-carbon homologation, by treatment with a titanocene(II) species under ethylene. The mode of the reaction is controlled by changing the ligands coordinated to titanocene(II).
Titanocene(II)-promoted reaction of anilides with thioacetals followed by treatment with a small amount of water gave reductivealkylation products, anilines with a secondary alkyl group.
Cyclopropanes were obtained by the titanocene(II)-promoted reaction of thioacetals with vinyl pivalate. It was also found that vinycyclopropanes were produced by a similar treatment of thioacetals with the titanocene(II) species in the presence of 1,3-dienes. (C) 2004 Elsevier Ltd. All rights reserved.