Steric factors direct Baylis-Hillman and aldol reactions in titanium tetrachloride mediated coupling between alpha-keto esters and cyclohex-2-enone derivatives.
The titanium tetrachloride mediated reaction of alpha-keto esters with 5,5-dimethylcyclohex-2-enone provides the corresponding Baylis-Hillman adducts exclusively whereas a similar reaction of alpha-keto esters with cyclohex-2-enone furnishes the corresponding aldol adducts (with high syn-diasteroeselectivity) as the major product (along with the Baylis-Hillman adducts as the minor product), thus clearly demonstrating the role of the steric factors in directing the reaction pathway.
Basavaiah
Deevi
D
School of Chemistry, University of Hyderabad, Hyderabad-500 046, India. dbsc@uohyd.ernet.in
Sreenivasulu
Bandaru
B
Rao
Anumolu Jaganmohan
AJ