Acetic Acid → 4-(2,2-Dimethoxy-ethylamino)-butyric acid tert-butyl ester

Participants

Reaction Steps

To a cooled solution (0° C.) of 2.94 g (15.00 mmol) of 4-aminobutyric acid ter-butylester; hydrochloride in 75 ml of MeOH were added 2.51 ml (18.00 mmol) of dimethoxyacetaldehyde (45% solution in TBME), 3.86 ml (15.00 mmol) of triethylamine, 16.75 g (135.00 mmol) of magnesium sulfate, 3.43 ml (60.00 mmol) of AcOH and 1.29 g (19.50 mmol) of sodium cyanoborohydride (1.99 g, 31.6 mmol). The reaction was stirred 2 h at RT, another 0.39 ml (1.50 mmol) of dimethoxyacetaldehyde (45% solution in TBME) was added and after 1.5 h, the reaction mixture was partitioned between aqueous saturated NaHCO3 and EtOAc/Et2O (1:1) (3×). The organic phases were washed with aqueous saturated NaHCO3, 10% NaCl and dried over Na2SO4 to yield after evaporation of the solvent 1.87 g (50%) of the titled compound as light yellow oil. MS: 248.18 (MH+).

Provenance & Evidence