4- Chloro-2 -furanone, formation

B. Holmbom, L. Kronberg, P. Bachlund, V. Langvic, J. Hemming, M. Reunanen, A. Smeds and L. Tikannen. Formation and properties of of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5J7)-furanone, a potent mutagen in chlorinated waters , in Water Chlorination Chemistry, Environmental Impact, and Health Effects (Eds. R. L. Jolley, L. W. Condie, J. D. Johnson,... 

Cyclopropyl isocyanates react effectively with various nucleophilic reagents. Ammonia and amines yield urea derivatives, " alcohols and phenols afford carbama-tg5,i5 5,164,181,184,185 )V )y-dimethylhydrazine gives a semicarbazide derivative, whereas cyclo-propylammonium chlorides are obtained in refluxing hydrochloric acid. The yields are usually very good. When more highly functionalized nucleophiles are employed, such as the enolate from ethyl 4-chloro-3-oxobutanoate, more complex molecules can be obtained, e.g. the formation of furanone derivative 15. ... 

Langvik, V.-A., O. Hormi, L. Tikkanen, and B. Holmbom. 1991. Formation of the mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone and related compounds by chlorination of phenolic compounds. Chemosphere 22, 547-555. 

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