Dimethylformamide dimethyl acetal → 3,9-Dimethyl-beta-carboline

Reaction equation

[CH3:1][C:2]1[N:3]=[CH:4][C:5]2[NH:6][C:7]3[C:12]([C:13]=2[CH:14]=1)=[CH:11][CH:10]=[CH:9][CH:8]=3.[CH3:15]OC(OC)N(C)C.N1(C2CCCCCCC2)CCCCCCN1>CN(C)C=O>[CH3:1][C:2]1[N:3]=[CH:4][C:5]2[N:6]([CH3:15])[C:7]3[C:12]([C:13]=2[CH:14]=1)=[CH:11][CH:10]=[CH:9][CH:8]=3

Participants

Procedure

0.182 g of 3-methyl-β-carboline (example 5), 0.5 ml of N,N-dimethylformamide-dimethylacetal (90%) and 0.02 g of diazabicyclooctane (Dabco) are stirred in 30 ml of absolute N,N-dimethylformamide for 15 hours at 110° C. The solvent is distilled off under vacuum and the residue is chromatographed on silica gel. (Methylene chloride/ethanol: 9+1). 0.095 g of 3,9-dimethyl-β-carboline with a 134° C. melting point (decomposition) is obtained.