Synthesis of novel spiro compounds using anthrone and pyrazole-5-thione moieties: A Michael addition approach

Article abstract of DOI:10.3184/030823407X237821

Novel routes for the synthesis of spiro derivatives anthrone have been designed using a Michael addition reaction followed by a Dieckmann condensation and Thorpe-Ziegler cyclisation. Bis-Michael addition of pyrazole-5-thione with 1,5-diarylpenta-1,4-dien-3-one gave directly a spiro derivative of pyrazole-5-thione. An enol lactone was synthesised by using mono Michael addition on dimedone, followed by hydrolysis and condensation.