2-Chloroaniline → 2-p-Tolylbenzoxazole
Reaction equation
[C:1]1([C:7]2[O:8][C:9]3[CH:15]=[C:14](C=O)[CH:13]=[CH:12][C:10]=3[N:11]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.Cl[C:19]1C=CC=CC=1N>>[C:4]1([CH3:19])[CH:3]=[CH:2][C:1]([C:7]2[O:8][C:9]3[CH:15]=[CH:14][CH:13]=[CH:12][C:10]=3[N:11]=2)=[CH:6][CH:5]=1Participants
Procedure
4.2 g (0.02 mole) of 2-(p-tolyl)-benzoxazole of the formula ##STR48## and 6.7 g (0.02 mole) of the Schiff's base, obtained from 2-phenyl-6-formyl-benzoxazole and o-chloroaniline, of the formula ##STR49## (melting point: 112.5°-113.5° C.) are dissolved in 80 ml of dimethyl formamide. To this solution are added in small amounts in the course of 20 minutes 2.1 g (0.002 mole) of sodium tert.butylate at 20° to 25° C. while introducing nitrogen. During the first 10 minutes, the reaction mixture is irradiated with ultraviolet light. While further introducing nitrogen and stirring for 2 hours at 20° to 25° C. the colour of the mixture changes gradually from yellow through violet brown to brown. Then 320 ml of methanol are added and the batch is cooled to 0° C. The precipitate is collected by filtration, washed repeatedly with a total of 40 ml of methanol and dried, affording 3.2 g (39% of theory) of 1-(2-phenyl-benzoxazol-6-yl)-2-(4'-benzoxazol-2-yl-phenyl)-ethylene of the formula ##STR50## in the form of a light beige-coloured powder with a melting point of 233°-237° C.
Sources & evidence
- ORD record
- ord-b308f6ce60c048ce82f1483930870989
- Source dataset
- uspto-grants-1979_09
- Patent number
- US04167628
Reaction notes
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