[N:1]1[CH:6]=[CH:5][N:4]=[CH:3][CH:2]=1.[O:7]1[CH2:12][CH2:11][CH2:10][CH2:9][CH:8]1[O:13][CH2:14][C:15]1[CH:20]=[CH:19][CH:18]=[C:17](N)[C:16]=1[CH3:22].N(OC(C)(C)C)=O>C1(C)C=CC=CC=1>[O:7]1[CH2:12][CH2:11][CH2:10][CH2:9][CH:8]1[O:13][CH2:14][C:15]1[CH:20]=[CH:19][CH:18]=[C:17]([C:2]2[CH:3]=[N:4][CH:5]=[CH:6][N:1]=2)[C:16]=1[CH3:22]A stirred solution of 50.0 g (0.624 mol) of pyrazine and 13.8 g (0.624 mol) of 3-amino-2-methylbenzenemethanol tetrahydropyranyl ether was warmed to 84° C.±6° C. and 9.6 g (0.094 mol) of t-butyl nitrite was added dropwise during 10 minutes. Upon complete addition, the reaction mixture was stirred at 85° C.±6° C. for 0.75 hours, then allowed to cool slowly to ambient temperature. The reaction mixture was dissolved in 100 mL of toluene, and subjected to column chromatography on silica gel, eluting with toluene-methylene chloride (3:1), methylene chloride, and finally ethyl acetate-methylene chloride (4:1). All the fractions were combined and subjected to a second column chromatography on silica gel, eluting with ethyl acetate-methylene chloride (1:19), ethyl acetate-methylene chloride (1:9), and ethyl acetate. The appropriate fractions were combined and concentrated under reduced pressure to give a residual oil. The oil was subjected to distillation under reduced pressure using a Kugelrohr distilling system to give 2.4 g of 2-methyl-3-(pyrazinyl)-benzenemethanol tetrahydropyranyl ether, b.p. 163° C.±3° C./0.04 mm.
Wird geladen…
