反应详情

To a stirred solution of 5.2 parts of 1-hydroxy-α-phenyl-1H-benzotriazole-6-methanol in 30 parts of dimethyl sulfoxide were added 0.96 parts of a sodium hydride dispersion 50%. The reaction mixture was stirred till no more hydrogen escapted. After the addition of 3.34 parts of ethyl 2-bromoacetate, the whole was stirred for 30 minutes at room temperature. 1.38 Parts of potassium carbonate were added and stirring was continued for 3 hours at 50° C. The dimethyl sulfoxide layer was evaporated and the residue was taken up in water and 20 parts of a hydrochloric acid solution 1N. The product was extracted with a mixture of trichloromethane and methanol (90:10 by volume). The extract was dried, filtered and concentrated. The concentrate was crystallized from 32.5 parts of dichloromethane. The product was filtered off and dried, yielding 3.1 parts (68.8%) of α-phenyl-1H-benzotriazole-5-methanol; mp. 143.0° C. (int. 70).

1. stirringstirring
2. waitwas continued for 3 hours at 50° C
3. customThe dimethyl sulfoxide layer was evaporated
4. extractionThe product was extracted with a mixture of trichloromethane and methanol (90:10 by volume)
5. customThe extract was dried
6. filtrationfiltered
7. concentrationconcentrated
8. customThe concentrate was crystallized from 32.5 parts of dichloromethane
9. filtrationThe product was filtered off
10. customdried