Indium(III) halides-catalyzed preparation of ferrocene-dihydropyrimidinones

Indium(III) halides (chloride and bromide) catalyse the three-component Biginelli coupling of ferrocenyl-1,3-diketones, aldehydes and urea (or thiourea) to give 5-ferrocenoyl-3,4-dihydropyrimidinones. 4-Ferrocenyl-3,4-dihydropyrimidinones were obtained from alkyl-acetoacetates, formylferrocene and urea. The tricyclic compound, 13-ferrocenecarbonyl-9-methyl-11-oxo-8-oxa-10,12-diazatricyclo [7.3.1.02,7]trideca-2,4-6-triene, was synthesized from 1-ferrocenyl-1,3-butanedione, salicilaldehyde and urea.