posted on 2008-03-06, 00:00authored byLuiz F. Silva,, Ramon S. Vasconcelos, Mário A. Nogueira
A versatile and metal-free approach for the synthesis of molecules bearing seven- and eight-membered rings is described. The strategy is
based on the ring expansion of 1-vinylcycloalkanols (or the corresponding silyl or methyl ether) mediated by the hypervalent iodine reagent
HTIB (PhI(OH)OTs). The reaction condition can be easily adjusted to give seven-membered rings bearing different functional groups. A route
to medium-ring lactones was also developed.