Dimethylformamide → 7-Thia-2,4,5-triazatricyclo(6.4.0.0,2,6)dodeca-1(12),3,5,8,10-pentaene

Temperature

160 °C

Five grams (30.0 mmoles) of o-chlorophenylisothiocyanate were dissolved in 50 ml. of dry DMF. A solution of 1.8 g. (30.0 mmoles) of formylhydrazine in 50 ml. of dry DMF was added dropwise rapidly to the stirred reaction mixture. The temperature of the reaction rose to about 45° C. The temperature was maintained between 60° C. and 100° C. for 24 hours. Thirty millimoles, 1.5 g., of sodium hydride as a 50% mineral oil suspension was added to the reaction mixture. The reaction was completed by heating at reflux temperature (160° C) for about 185 hours. The cooled mixture was poured into water. The aqueous mixture was extracted with n-hexane to remove mineral oil. The product was extracted with ethyl acetate. The ethyl acetate extract was washed (water), dried (MgSO4) and evaporated in vacuo to a residual oil. the oil was covered with dry ether an the product crystallized upon standing. The yield of s-triazolo[3,4-b]benzothiazole, m.p. about 175°-176° C., was 200 mg.

1. customrose to about 45° C
2. temperatureThe temperature was maintained between 60° C. and 100° C. for 24 hours
3. temperatureby heating
4. extractionThe aqueous mixture was extracted with n-hexane
5. customto remove mineral oil
6. extractionThe product was extracted with ethyl acetate
7. extractionThe ethyl acetate extract
8. washwas washed (water)
9. dry with materialdried (MgSO4)
10. customevaporated in vacuo to a residual oil
11. customcrystallized

ORD record

ord-23156dacf8c6489f9b9a6d11efa89586

Source dataset

uspto-grants-1978_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04082762