Formaldehyde → 1,1-Dimethylethyl (2R,6S)-2,6-dimethyl-4-{[4-(methylamino)phenyl]methyl}-1-piperazinecarboxylate

Participants

Reaction Conditions

Reaction Steps

The title compound was prepared from 1,1-dimethylethyl (2R,6S)-4-[(4-aminophenyl)methyl]-2,6-dimethyl-1-piperazinecarboxylate (D28) using a method similar to that described for D23 in Description 23A although the reaction was heated at 50° C. for 48 h prior to addition of sodium borohydride then for 1 h after addition. Further paraformaldehyde (1 eq) and sodium methoxide (1 eq) were added; the reaction was heated at 50° C. for 12 h; further sodium borohydride (1 eq) was added and the reaction heated at 50° C. for 1 h. δH (CDCl3, 400 MHz) 7.16 (2H, d), 6.57 (2H, d), 4.05 (2H, m), 3.70 (1H, br s), 3.36 (2H, s), 2.82 (3H, s), 2.59 (2H, d), 2.06 (2H, dd), 1.49 (9H, s), 1.27 (6H, d). MS (ES): 356.3, (MNa+), 234.3, no molecular ion (MH+) observed.

Provenance & Evidence