70172-92-8Relevant articles and documents
Remarkably Selective Chlorination of Phthalic Anhydride and Its Monochlorinated Derivatives
Verbicky, John W.,Williams, Louella
, p. 2465 - 2468 (1983)
The vapor-phase chlorination of phthalic anhydride 1 and its monochlorinated derivatives 2 and 3 in the temperature range from 390 to 600 deg C with elemental chlorine has been investigated and found to be highly selective.Thus, chlorination of 1 in the temperature range from 390 to 450 deg C was found to give high yields of monochlorinated products accompanied by only small amounts of dichlorination with a high degree of regioselectivity favoring the formation of 4-chlorophthalic anhydride.Chlorination of a 3-chlorophthalic anhydride 3 by this method has provided thefirst direct synthesis of 3,5-dichlorophthalic anhydride 7 from phthalic anhydride via chlorination.