The synthesis of unusual isocoumarin derivatives:: the chemistry of homophthalic acid

Homophthalic acid was reacted with thionyl chloride/DMF and ethyl chloroformate/NEt3 in the presence and absence of NaN3. In all cases completely different isocoumarin derivatives were obtained. These unusual isocournarin derivatives were characterized and their mechanism of formation is discussed. (c) 2007 Elsevier Ltd. All rights reserved.