Hydrazine hydrate (1:1) → HCID 178422445, compound

Participants

Reaction Steps

2.80 g (10 mmol) of the title compound of Step B and 1.79 g(15 mmol) of N,N-dimethylformamide dimethyl acetal were dissolved in 16 mL of ethyl acetate and heated to reflux. The methanol/ethyl acetate mixture was removed via a Dean Stark trap and was replaced with fresh ethyl acetate. After heating to reflux for 4 hours, the reaction was cooled to room temperature and allowed to stand overnight. It was then reluxed further for 2 hours, cooled to 60° C., and 0.75 g (15 mmol) of hydrazine monohydrate was added. The reaction was reheated to reflux for 1 hour, cooled to room temperature, and diluted to 100 mL with ethyl acetate. The organic phase was washed twice with 100 mL of water, dried over magnesium sulfate, and concentrated under reduced pressure to yield 3.10 g of an oily yellow solid. This solide was triturated with hexanes, collected by filtration, washed further with hexanes, and dried to yield 2.79 g of the title compound of Step C as a pale yellow solid melting at 162-164° C. 1H NMR (CDCl3): δ2.34 (s, 3H), 2.79 (s, 3H), 3.84 (s, 2H), 7.35 (s, 1H), 7.46 (s, 1H), 10.4 (br s).

Provenance & Evidence