Useful Syntheses of Heterocycles Various Heterocyclic Scaffolds

4 Useful Syntheses of Heterocycles Various Heterocyclic Scaffolds 

SCHEME 13.49 Proposed mechanism for the formation of 5-hydroxy-2//-pyrrol-2-ones 202 by Quai et al. [86]. 

SCHEME 13.50 (a) Three-component thiazole 209 synthesis by Renuga et al. and (b) the proposed mechanism for its formation [87]. 

Heydari and Tahamipour reported a Knoevenagel conden-sation/cychzation sequence of certain 1,10-phenanthrolinium 

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