Interplay of Theory and Experiment: Reversal of the Torquoselectivity of the Electrocyclic Ring Opening of 3-Acetylcyclobutene by a Lewis Acid.
Theoretical predictions, accompanied by firm experimental verification, are presented on the "torquoselectivity" of the thermal ring opening of 3-acetylcyclobutene (1). 3-Acetylcyclobutene was synthesized from commercially available 1,1-cyclobutanedicarboxylic acid. Thermolysis of 3-acetylcyclobutene resulted in a mixture of E- and Z-dienes with a slight preference for the E-diene. This preference was reversed by the Lewis acid, ZnI(2), as predicted from theoretical calculations.
Niwayama
Satomi
S
Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California 90095.