A greener procedure for the synthesis of [Bu4N]2-cis-[Ru(4-carboxy-4′-carboxylate-2,2′-bipyridine)2(NCS)2] (N719), a benchmark dye for DSSC applications†
Abstract
A previously reported protocol for the synthesis of the commercial dye [Bu4N]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.