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Updated: Sep 20, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Green protocol for conjugate addition of thiols to alpha,beta-unsaturated ketones using a [bmim]PF6/H2O system
J S Yadav1, B V S Reddy, Gakul Baishya
1Division of Organic Chemistry, Indian Institute of Chemical Technology, Hyderabad-500 007, India. yadav@iict.ap.nic.in
Abstract:
Alpha,beta-unsaturated ketones undergo conjugate addition rapidly with thiols in a hydrophobic ionic liquid [bmim]PF(6)/H(2)O solvent system (2:1) in the absence of any acid catalyst to afford the corresponding Michael adducts in high to quantitative yields with excellent 1,4-selectivity under mild and neutral conditions. The enones show enhanced reactivity in ionic liquids, thereby reducing reaction times and improving the yields significantly. The use of ionic liquids helps to avoid the use of either acid or base catalysts for this conversion. The recovered ionic liquid was reused four to five times with consistent activity.
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