Formamidine acetate → 6-[(4-Chlorophenyl)-(1,2,4-triazol-1-yl)methyl]-1-methylbenzotriazole

Participants

Reaction Steps

A mixture of 5 g of intermediate 4-a, 4.8 g of methanimidamide monoacetate and 15 ml of methanol was stirred for 1.5 hours at reflux temperature. After cooling to room temperature, the reaction mixture crystallized and there were added 30 ml of water. After stirring for 1 hour the precipitate was filtered off, washed with water and dried in vacuo at 50° C. The product was diluted with 11.8 ml of 2-propanol and the whole was treated with active charcoal for 15 min. at reflux temperature. The charcoal was filtered off while hot and washed with 2-propanol. The product was crystallized, filtered off and dried in vacuo at 50° C., yielding 3.3 g (66.0%) of (+)-6-[(4-chloro-phenyl)-(1H-1,2,4-triazol-1 -yl) methyl]-1-methyl-1H-benzotriazole (comp. 1-a); mp. 130°-135° C.; [α]D20 =+8.0° (conc.=10% in CH3OH); enantiomeric excess: 98.4%.

Provenance & Evidence