3-Oxo-azetidine-1-carboxylic acid tert-butyl ester → tert-butyl 3-[9-[1-(4-amino-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl]-7-chloro-6-cyano-2,3-dihydro-1,4-benzoxazepin-4(5H)-yl]azetidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

9-[1-(4-amino-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl]-7-chloro-2,3,4,5-tetrahydro-1,4-benzoxazepine-6-carbonitrile bishydrochloride (0.030 g, 0.078 mmol) was dissolved in methanol (3.0 mL), and the tert-butyl 3-oxoazetidine-1-carboxylate (0.027 g, 0.16 mmol) and then sodium cyanoborohydride (0.0098 g, 0.16 mmol) were added. The reaction was heated to 60° C. for 3 hrs and then allowed to cool to room temperature. The reaction was diluted with ethyl acetate and washed with brine. The organic layer dried over magnesium sulfate and concentrated to give the crude product as an amber oil. The oil was purified by prep HPLC on a C-18 column eluting water:acetonitrile gradient at pH 10 to give tert-butyl 3-[9-[1-(4-amino-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl]-7-chloro-6-cyano-2,3-dihydro-1,4-benzoxazepin-4(5H)-yl]azetidine-1-carboxylate (0.015 g, 35%). LCMS calculated for C26H32ClN8O3 (M+H)+: m/z=539.2; found: 539.2.

Provenance & Evidence