Hydrazine hydrate (1:1) → HCID 178505619, compound

Participants

Reaction Conditions

Reaction Steps

A little DMAP and 238 mg (4.75 mmol) of hydrazine hydrate are added to a solution of 1.35 g (4.75 mmol) of 1-(3,5-dichloropyridin-2-yl)-2-(2-fluorophenyl)ethanone from example 2A in 12 ml of pyridine. The mixture is heated in a closed vessel in a microwave at 160° C. for 20 min and then concentrated in vacuo, and the residue is purified by chromatography on silica gel (eluent: dichloromethane/methanol 100:3). 507 mg (41% of theory) of the title compound and 388 mg of the uncyclized hydrazone are obtained. The latter is heated anew in 5 ml of DMF in the microwave at 200° C. for 1.5 h. The solution is concentrated and the residue is purified by preparative HPLC. A further 176 mg (12% of theory) of the title compound are obtained in this way.

Provenance & Evidence