Piperonyl alcohol → 2(R)-[(3,4-methylenedioxybenzyl)-(4-methoxy-2,3,6-trimethylbenzenesulfonyl)amino]-3-methylbutyric acid benzyl ester

Participants

Reaction Steps

To a mixture of 2(R)-(4-methoxy-2,3,6-trimethylbenzenesulfonylamino)-3-methylbutyric acid benzyl ester (4.5 g, 10.72 mmol), 3,4-(methylenedioxy)phenylmethanol (2.04 g, 13.41 mmol), and tributylphosphine (3.35 mL, 13.4 mmol) in dry benzene (60 mL) cooled in an ice bath was added 1,1′-(azodicarbonyl)dipiperidine (3.38 g, 13.4 mmol). The reaction mixture was stirred overnight to room temperature and then flash chromatographed on a silica gel column (5-10% ethyl acetate/hexanes) to give 2(R)-[(3,4-methylenedioxy-benzyl)-(4-methoxy-2,3,6-trimethylbenzenesulfonyl)amino]-3-methylbutyric acid benzyl ester (4.8 g) as a white solid.

Provenance & Evidence