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Please login to access the full content or check if you have access via Variation 1: Kinetic Deprotonation of a Ketone

DOI: 10.1055/sos-SD-032-00588

Trauner, D.Science of Synthesis, (200832549.

The deprotonation of ketones can often be achieved with a high level of control. Regioselectivity issues arise when unsymmetrical ketones have α-protons available on both sides of the carbonyl group. These can be overcome by deprotonating under kinetic or thermodynamic conditions. Kinetic enolates are formed by deprotonation at the least-hindered and kinetically most-acidic site, which usually leads to less substituted and thermodynamically less stable enolates. In the case of enones and vinylogous esters, the position next to the carbonyl group undergoes faster deprotonation under kinetic conditions (α- vs γ-deprotonation). The regioselective formation of kinetic enolates has been studied and reviewed in great detail, and some examples are given in Scheme 3.[‌6‌‌9‌]

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