Diastereoselective hydrogenation of o-toluic acid derivatives over supported rhodium and ruthenium heterogeneous catalysts

Abstract

Asymmetric hydrogenation of an o-toluic acid derivative to 2-methylcyclohexanoic acid with high optical selectivity (up to 95%) was performed by using (S)-pyroglutamic acid methyl ester as a chiral auxiliary and Rh–Al₂O₃ as the catalyst.

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