反应详情

Following the general procedure for the transacetalization reaction of Description 6, 6.6 g (49.2 mmol) of (2R)-3,3-dimethylbutane-1,2,4-triol (6) was reacted in 120 mL of dichloromethane (DCM) in the presence of 2.51 g (10.0 mmol) of PPTS with 11.3 mL (11.4 g, 75.0 mmol) of benzaldehyde dimethyl acetal. Purification by silica gel column chromatography using diethylether (Et2O) and hexane (Hxn) mixtures as eluent (Et2O/Hxn=2:3→Et2O/Hxn=1:1→Et2O/Hxn=3:2) provided 4.9 g (45% yield) of the title compound (7a) as a colorless liquid. Rf=0.44 (Et2O/Hxn=2:3). 1H NMR (400 MHz, CHCl3): δ=0.86 (s, 3H), 1.16 (s, 3H), 2.02-2.06 (m, 1H), 3.60-3.64 (m, 1H), 3.68-3.72 (m, 4H), 5.52 (s, 1H), 7.33-7.41 (m, 3H), 7.49-7.53 (m, 2H) ppm. MS (ESI) m/z: 223.0 (M+H)+, 245.0 (M+Na)+. The analytical data for the compound was consistent with that given in the literature.

1. customPurification by silica gel column chromatography