Vi. Potkin et al., Reaction of 4-ethoxy-2-(2,3,3-trichloro-1-nitro-2-propenylidene)benzazetine with methyl- and phenyllithium, RUSS J ORG, 37(5), 2001, pp. 640-643
The reactions of 4-ethoxy-2-(2,3,3-trichloro-1-nitro-2-propenylidene)benzaz
etine with methyl- and phenyllithium at a ratio of 1:2 result in replacemen
t of one chlorine atom and formation, respectively, of 4-ethoxy-2-(2,3-dich
loro-3-methyl-1-nitro-2-propenylidene)benzazetine and 4-ethoxy-2-(2,3-dichl
oro-1-nitro3-phenyl-2-propenylidene)benzazetine in 45 and 52% yield. With e
xcess phenyllithium (reactant ratio 1:5), a mixture of products is formed d
ue to replacement of one, two, and three chlorine atoms by phenyl groups. A
n analogous reaction with methyllithium is nonselective.