Thallium trinitrate mediated ring contraction of monocyclic ketones: Stereochemical aspects
摘要:
The reaction of 3- and 4-alkylcyclohexanones with thallium trinitrate (TTN) leads to the alkylcyclopentanecarboxylic acids in good yields and with high degree of stereoselectivity. The ring contraction of 2-methylcyclohexanone gives poor yields and 2,6-dimethylcyclohexanone does not undergo contraction. The observed diastereoselectivities of the reactions agree with the mechanism proposed by McKillop et al. (C) 1997 Elsevier Science Ltd.