Methylhydrazine → N-methylbenzothiohydrazide

Bromobenzene (1.6 g, 10 mmol) was added into 25 ml anhydrous THF solution containing magnesium powder (0.3 g, 12.5 mmol), and refluxed for 2 hr. After it was cooled, the clear reaction solution was added into carbon disulfide (1 ml, 16.8 mmol) at 0° C., and stirred for 30 min at rt. The resulting mixture was then added into methylhydrazine (1.6 ml, 30 mmol) at 0° C., and stirred for another 2 hours. To this solution was added water (15 ml) and extracted with EtOAc (30 ml×3). The organic solution was concentrated to minimum volume, and subjected to silica gel column chromatography (eluant: 1:3-1:1 ethyl acetate: hexanes) to give thiobenzoic acid N-methyl hydrazide (0.72 g, total yield: 48%). 1H NMR (CDCl3) δ 3.3 (s, 3H), 6.0 (s, 2H), 7.3-7.4 (m, 5H); ESMS calcd (C8H10N2S): 166.1; found: 167.1 (M+H)+.

1. temperaturerefluxed for 2 hr
2. temperatureAfter it was cooled
3. stirringstirred for another 2 hours
4. extractionextracted with EtOAc (30 ml×3)
5. concentrationThe organic solution was concentrated to minimum volume

ORD record

ord-25baa33a4d414ef293e0df7fa666df80

Source dataset

uspto-grants-2004_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06800660B2