Stereoselective synthesis of (3R,4S)-3-methoxy-4-methylaminopyrrolidine

A short, efficient, and stereoselective total synthesis of a pyrrolidine alkaloid: (-)-codonopsinine

An efficient total synthesis of antibiotic (-)-codonopsinine 1 with an overall yield of 44% was achieved from d-alanine as a chiral template. The key steps in our strategy are modified Sharpless asymmetric dihydroxylation reaction and the highly stereoselective intramolecular acid-catalyzed amidocyclization.

Asymmetric synthesis of 3,4-anti- and 3,4-syn-substituted aminopyrrolidines via lithium amide conjugate addition

The diastereoselective conjugate addition of homochiral lithium amides to methyl 4-(N-allyl-N-benzylamino)but-2-enoate has been used as the key step in a simple and efficient protocol for the preparation of 3,4-substituted aminopyrrolidines. This protocol provides a complementary and stereoselective route to both anti- and syn-3-amino-4-alkylpyrrolidines as well as anti- and syn-3-hydroxy-4-aminopyrrolidines, in high de and ee viabeta-amino enolate functionalisation. This methodology has been applied to the synthesis of anti-(3S,4S)- and syn-(3R,4S)-3-methoxy-4-(N-methylamino)pyrrolidine.

Lithium amide conjugate addition for the asymmetric synthesis of 3-aminopyrrolidines

Conjugate addition of homochiral lithium amides to methyl 4-(N-benzyl-N-allylamino)but-2-enoate, chemoselective N-deprotection and concomitant cyclisation, followed by enolate functionalisation and deprotection allows access to syn- and anti-3,4-disubstituted aminopyrrolidines in > 98% d.e. and > 98% e.e.