H. Sun, Y. Kao
1981
Citations
0
Influential Citations
0
Citations
Journal
Acta Chimica Sinica
Abstract
The titled compound 3-methoxy-4-chloro-5-nitrobenzonitrile (5), a useful ntermediate ur attempted synthesis of the C_9-N fragment of maytansine, was formerly prepared by us from -ethoxy-6-nitroaniline. We now report a new synthesis of it from vanillin.5-nitrovanillin (2), hen refluxed with phosphoryl ohloride and s-collidine in toluene, gave 3-methoxy-4-ohloro-5-itrobenzylidene diohloride (3) instead of 3-methoxy-4-ohloro-5-nitrobenzaldehyde (4) as was eported by Grundon[4], while the reaction of 2 with thionyl ohloride and DMF at room emperature gave 3-methoxy-4-hydroxy-5-nitrobenzylidene diohloride (6). 3 gave 4 when treated ith ooncentrated sulfuric acid at room temperature and 4 was converted to the desired oompound hen heated in 85% formic aoid with hydroxylamine hydrochloride and sodium formate.