反应详情

To a stirred, refluxing solution of 5.00 g of 2,3-dicyano-5,6-dichloropyrazine in 100 ml of o-dichlorobenzene under nitrogen was added dropwise 10.00 g of methyl diphenylphosphinite. After the addition was completed, the mixture was refluxed for 4 hours and then allowed to stand overnight. The resulting solid was separated by filtration, washed with benzene and twice with hexane, recrystallized from 200 ml of o-dichlorobenzene, and dried at 80° C./0.1 mm (13 Pa) to give 8.08 g of 2,3-dicyano-5,6-bis(diphenylphosphinyl)pyrazine (shown by formula in claim 4) as a white solid, decomposition beginning at 210° C. Anal. calcd for C30H20N4O2P2 : C, 67.93; H, 3.80; N, 10.56; P, 11.68. Found: C, 67.77; H, 3.92; N, 10.48; P, 11.18.

1. additionAfter the addition
2. temperaturethe mixture was refluxed for 4 hours
3. customThe resulting solid was separated by filtration
4. washwashed with benzene and twice with hexane
5. customrecrystallized from 200 ml of o-dichlorobenzene
6. customdried at 80° C./0.1 mm (13 Pa)