In 2018,Maezono, Shizuka Mei Bautista; Park, Ga Eul; Lee, Yong Rok published 《Regiospecific construction of diverse and polyfunctionalized γ-pyrone cores by indium(III)-catalyzed annulation of diazodicarbonyls with active methylenes, 4-hydroxycoumarins, or 4-hydroxyquinolinone》.Organic Chemistry Frontiers published the findings.Synthetic Route of Br3In The information in the text is summarized as follows:
An efficient and novel construction of diverse and polyfunctionalized γ-pyrones has been developed by InBr3-catalyzed annulation of various cyclic and acyclic diazo compounds with multifarious active methylenes, 4-hydroxycoumarins, or 4-hydroxyquinolinone. This technique proceeds through a cascade of carbene generation/ketene formation/conjugate addition/intramol. cyclization/elimination reactions. In addition, transformation of the synthesized compound for further functionalization is realized.Indium(III) bromide(cas: 13465-09-3Synthetic Route of Br3In) was used in this study.
Indium(III) bromide(cas: 13465-09-3) is used in organic synthesis as a water tolerant Lewis acid. It efficiently catalyzes the three-component coupling of β-keto esters, aldehydes and urea (or thiourea) to afford the corresponding dihydropyrimidinones.Synthetic Route of Br3In
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary