Methyl 2-oxocycloheptane-1-carboxylate → 2-(N'-allyl-N'-cyclobutyl-hydrazino)-cycloheptanecarboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

N′-Allyl-N′-cyclobutyl-hydrazine hydrochloride (2.01 g, 12.37 mmol) was dissolved in methanol (40 mL). 2-Oxo-cycloheptanecarboxylic acid methyl ester (1.93 mL, 12.37 mmol), sodium acetate (2.04 g, 24.74 mmol), sodium cyanoborohydride (1.55 g, 24.74 mmol) and 4 Å molecular sieves (2.80 g) were added sequentially. The reaction was stirred at 25° C. for 18 h before it was quenched via the addition of saturated aqueous sodium bicarbonate solution (30 mL). The mixture was extracted with ethyl acetate (3×40 mL). The organic layers were combined, dried over magnesium sulfate, filtered and concentrated in vacuo to afford the crude product, 2-(N′-allyl-N′-cyclobutyl-hydrazino)-cycloheptanecarboxylic acid methyl ester, as a yellow oil. The residue was used directly in the next step. LC-MS (ESI) calcd for C16H28N2O2 280.41, found 281.2 [M+H+].

Provenance & Evidence