L. Fitjer, W. Schlotmann, M. Noltemeyer
Jul 10, 1995
Citations
0
Influential Citations
5
Citations
Journal
Tetrahedron Letters
Abstract
Abstract Cyclobutyl phenyl sulfide 2 , cyclobutyl phenyl sulfoxide 3 and ( SR )-cyclobutyl p-tolyl sulfoxide (SR)- 8 have been synthesized and used for the spiroannelation of cyclopentanone. In the most effective sequence, lithiated 3 is added to ketones with formation of β-hydroxy sulfoxides 4a-g , which are ring enlarged and hydrolyzed to cyclopentanones 6a-e and sulfanylcyclopentene 6f , respectively, after reduction to β-hydroxy sulfides 5a-f . In an asymmetric version using (SR)- 8 , partial racemization during ring enlargement was observed.