An efficient synthesis of quaterrylenedicarboximide NIR dyes.

Quaterrylenedicarboximides were prepared from 9-bromoperylene-3,4-dicarboximides by palladium-catalyzed coupling with 3-perylene boronic ester, followed by oxidative cyclodehydrogenation of the resulting perylene-perylenedicarboximide dyads with iron(III) chloride. The quaterrylenedicarboximides, described here, are highly photochemically and thermally stable dyes, which may be useful as green NIR dyes (lambdamax = 735 nm) and as building blocks for the synthesis of higher rylene dyes.