Synthesis of cyclohepta-1,3,5-trienes by the reaction of aromatic hydrocarbons with diazo compounds in the presence of transition metal complexes
摘要:
A preparative method has been developed for the synthesis of cyclohepta-1,3,5-trienes, using the reaction of aromatic hydrocarbons with diazomethane, methyldiazoacetate, adamantanoyldiazomethane, and 1-diazo-3-phenylpropan-2-one, with rhodium trifluoroacetate as catalyst. The order of activity and the relative reactivity coefficients of substituted benzenes have been determined, and the link between these characteristics and the energy of the highest occupied molecular orbital of the aromatic ring has been established. In catalyzed reactions of benzenes with diazomethane or methyldiazoacetate, leading to cycloheptatrienes, effects of chemical polarization of the ring have not been observed.