反应详情

To an ice-cold solution of 4 g of 5,6,7,8-tetrahydro-5-hydroxymethylene-1-methyl-4(1H) cycloheptapyrazolone in 130 ml of methanol was added, dropwise, a solution of 1.1 ml of methylhydrazine in 20 ml of methanol and the mixture was heated at reflux for 2.5 hours. Removal of the solvent under reduced pressure left a residual dark oil. The oil was flash chromatographed (7.5% 2-propanol in methylene chloride) to give 4,5,6,7-tetrahydro-1,7-dimethyl-1H-cyclohepta[1,2-c:3,4-c']dipyrazole as a yellow crystalline solid melting at about 94°-96° C. The chromatography also gave 4,5,6-tetrahydro-2,7-dimethyl-2H-cyclohepta[1,2-c:3,4-c')]dipyrazole melting at about 119°-121° C.

1. temperatureat reflux for 2.5 hours
2. customRemoval of the solvent under reduced pressure
3. waitleft a residual dark oil
4. customchromatographed (7.5% 2-propanol in methylene chloride)