Lewis acid reversal of the torquoselectivity of the electrocyclic ring opening of 3-acetylcyclobutene
摘要:
Thermolysis of 3-acetylcyclobutene resulted in a mixture of E-and Z-dienes, favoring slightly the E-diene, in accord with theoretical prediction. This preference was reversed by the Lewis acid, ZnI2, also predicted by ab initio calculations on a model system.
Interplay of Theory and Experiment: Reversal of the Torquoselectivity of the Electrocyclic Ring Opening of 3-Acetylcyclobutene by a Lewis Acid
摘要:
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, ZnI2, as predicted from theoretical calculations.