Efficient and Highly Enantioselective Construction of Trifluoromethylated Quaternary Stereogenic Centers via High-Pressure Mediated Organocatalytic Conjugate Addition of Nitromethane to β,β-Disubstituted Enones

A very effective high-pressure-induced
acceleration of asymmetric
organocatalytic conjugate addition of nitromethane to sterically congested
β,β-disubstituted β-CF3 enones has been
developed. A combination of pressure (8–10 kbar) and noncovalent
catalysis with low-loading of chiral tertiary amine-thioureas (0.5–3
mol %) is shown to provide very efficient access to a wide range of
γ‑nitroketones containing trifluoromethylated all-carbon
quaternary stereogenic centers in the β-position (80–97%,
92–98% ee).