A greener procedure for the synthesis of [BuN]--[Ru(4-carboxy-4′-carboxylate-2,2′-bipyridine)(NCS)] (N719), a benchmark dye for DSSC applications

A previously reported protocol for the synthesis of the commercial dye [Bu 4 N] 2 [Ru(4-carboxy-4′-carboxylate-2,2′-bipyridine) 2 (NCS) 2 ] (N719) was thoroughly optimized in terms of the amount of input materials needed, reaction times and temperatures achieving significant reductions in all the three synthetic steps. This optimization allowed a 81% reduction of the Sheldon's E factor of the overall process. A previously reported protocol for the synthesis of the commercial dye N719 was thoroughly optimized in terms of the amount of input materials needed, reaction times and temperatures achieving significant reductions in all the three synthetic steps.