Acetic Acid → Methyl 4-[2-({[(1,1-dimethylethyl)oxy]carbonyl}amino)ethyl]-3-thiomorpholinecarboxylate 1,1-dioxide

Participants

Reaction Steps

To a stirred solution of methyl 3-thiomorpholinecarboxylate 1,1-dioxide (D16; 1.08 g, 5.6 mmol) in 14 ml of anhydrous 1,2-dichloroethane was added N-boc-2-aminoacetaldehyde (1.1 g, 6.7 mmol) and acetic acid (0.316 ml, 5.6 mmol). After 30 min. sodium triacetoxyborohydride (1.78 g, 8.4 mmol) was added and the solution stirred at room temperature. Additional aliquots of N-boc-2-aminoacetaldehyde and sodium triacetoxyborohydride (1.0 g, 4.7 mmol) were added and the reaction continued overnight. The solvent was removed under reduced pressure and the residue was purified by SCX column, followed by chromatography (silica, cyclohexane:ethyl acetate 70:30 to 1:1) and again SCX, to give 295 mg of the target compound.

Provenance & Evidence