Synthesis of 2,2′-diamino-7-tert-butyl-9,9′-spirobifluorene starting from 4,4′-di-tert-butylbiphenyl

Abstract

A novel spirobifluorene diamine monomer, 2,2 0 -diamino-7-tert-butyl-9,9 0 -spirobifluorene, was obtained starting from the readily available reagent 4,4 0 -di-tert-butylbiphenyl. The key step of the synthesis is the introduction of a nitro group into the 2-position of the spirobifluorene through the loss of tert-butyl at the 2-position.