The syntheses of indanones and indenones via rhodium catalyzed carbonylative arylation of alkynes

Abstract

Indanones and indenones are important classes of compounds in organic chemistry. These structural motifs are found in various types of natural compounds and also can be used as intermediates in the synthesis of a variety of molecules.In this study, indanones and indenones were synthesized via rhodium catalyzed reaction of alkynes with arylboroxines under a CO atmosphere. Reactions were performed using para- and meta- substituted phenylboroxines. Higher yields were obtained for indanones with methyl- substitution on para- and meta-positions of phenylboroxines than methoxy-substituted ones. However, by using phenylboroxine with an electron withdrawing group, a lower yield of indanone was observed. Higher yields of indanone were obtained with electron poor diaryl acetylenes than electron rich ones.As a general result, the yields of indanone were higher than the yields of indenones at the end of the reaction. The desired products were purified with silica gel column chromatography and the structure of indanones and indenones were determined using GC, GC-MS, NMR, FT-IR and HRMS techniques.