Tetrahydrofuran → di-tert-butyl (2S)-2-(((3S)-3-methyl-4-morpholinyl)methyl)-1,4-piperazinedicarboxylate

Participants

Reaction Conditions

Reaction Steps

A 250-mL round-bottomed flask was charged with di-tert-butyl (2R)-2-(((3S)-3-methyl-4-morpholinyl)carbonyl)-1,4-piperazinedicarboxylate (2.55 g, 6.17 mmol, step 1), BH3.THF (1.0 M in THF, 19.0 mL, 19.0 mmol, Sigma-Aldrich, St. Louis, Mo.) and THF (100 mL). The mixture was stirred at 50° C. for 15 h. The mixture was allowed to cool to room temperature and then additional BH3.THF complex (1.0 M in THF, 5.0 mL, 5.0 mmol) was added. The reaction mixture was heated at 50° C. for 1 h. The mixture was allowed to cool to room temperature and then MeOH was added slowly until bubbling ceased. The reaction mixture was concentrated to give di-tert-butyl (2S)-2-(((3S)-3-methyl-4-morpholinyl)methyl)-1,4-piperazinedicarboxylate (2.5 g) as a white solid.

Provenance & Evidence