A highly efficient resolution protocol for 2′-halo-α-methylbenzylamines

Chemical Resolution of Dl-Phenylalanine Methyl Ester Using N-Acetyl-D-Phenylglycine as Resolving Agent

An improved method for chemical resolution of DL-phenylalanine methyl ester using N-acetyl-D-phenylglycine as a resolving agent is described. This new resolving agent is readily available, non-toxic and easily recoverable from the insoluble diasteromeric salt. This method was used to obtain D-phenylalanine methyl ester with high optical purity of 98.1% and a high yield of 81.2%.

Asymmetric synthesis of nonracemic primary amines via spiroborate-catalyzed reduction of pure (E)- and (Z)-O-benzyloximes: applications toward the synthesis of calcimimetic agents

Highly enantiopure (1-aryl)- and (1-naphthyl)-1-ethylamines were synthesized by the borane-mediated reduction of single-isomeric (E)- and (Z)-O-benzyloxime ethers using the stable spiroborate ester derived from (S)-diphenyl valinol and ethylene glycol as the chiral catalyst. Primary (R)-arylethylamines were prepared by the reduction of pure (Z)-ethanone oxime ethers in up to 99% ee using 15% of catalyst. Two convenient and facile approaches to the synthesis of new and known calcimimetic analogues employing enantiopure (1-naphthalen-1-yl)ethylamine as chiral precursor are described.