Synthesis of the β<sub>3</sub>-Adrenergic Receptor Agonist Solabegron and Analogous <i>N</i>-(2-Ethylamino)-β-amino Alcohols from <i>O</i>-Acylated Cyanohydrins – Expanding the Scope of Minor Enantiomer Recycling
A novel methodology to produce highly enantioenriched N-(2-ethylamino)-beta-amino alcohols was developed. These compounds were obtained from O-(alpha-bromoacyl) cyanohydrins, which were synthesized by the minor enantiomer methodology employing a Lewis acid and a biocatalyst, followed by nucleophilic substitution with amines and reduction. The importance of the developed methodology was demonstrated by completing a highly enantioselective total synthesis of the beta(3)-adrenergic receptor agonist Solabegron.