Ethylene Glycol → 2(3H)-Benzothiazolone, 4-methyl-, hydrazone

Temperature

140 °C

4-Methyl-2-aminobenzothiazole (8.21 g.; 0.05 mole), hydrazine monohydrochloride (1.14 g.; 0.017 mole), 85% hydrazine hydrate (1.96 g.; 0.033 mole), and 41 ml. of ethylene glycol were mixed, and the mixture heated under N2 atmosphere to 140°C. These reaction conditions were continued for 15 hours; the reaction mixture was then permitted to cool slowly to romm temperature and, for convenience only, stored overnight under N2 atmosphere. Water (45 ml.) was added to the reaction mixture in the morning to force crystallization. The reaction mixture was then filtered to separate the desired 4-methyl-2-hydrazinobenzothiazole compound. It was dried in vacuo overnight at 60°C. The yield was 8.00 g., 89% yield, m.p. 143°-51°C. Non-aqueous titration showed the product to be 85.8% pure.

1. customThese reaction conditions
2. temperatureto cool slowly
3. waitfor convenience only, stored overnight under N2 atmosphere
4. customcrystallization
5. filtrationThe reaction mixture was then filtered
6. customto separate the desired 4-methyl-2-hydrazinobenzothiazole compound
7. customIt was dried in vacuo overnight at 60°C

ORD record

ord-dec3b19a4e2941c0855485bbb8519257

Source dataset

uspto-grants-1976_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03937714