Reactions of 1-methyl-4-t-butylcyclohexene and 1-methylcyclohexene with thallium(I) acetate–iodine

Abstract

Treatment of 1-methyl-4-t-butylcyclohexene (2) with thallium(I) acetate–iodine in wet acetic acid at 90 °C gives a complex mixture of products, which differs from that obtained from a Woodward reaction with silver(I) acetate followed by hydrolysis and which includes the unexpected hydroxy-iodoacetate (25). At 20 °C the thallium(I)-mediated reaction gives a mixture of regioisomeric iodo-acetates. A re-investigation of the reaction of thallium(I) acetate-iodine with 1-methylcyclohexene (1) at 20 °C has shown that this is not highly regioselective as reported earlier.The actions of KOAc–l2–18-crown-6 and of iodine(III) triacetate in acetic acid on the alkenes (1) and (2), and of I2–H2O in tetramethylene sulphone–chloroform on the alkene (2) are reported.