The synthesis and characterization of novel phenylene bridged boron−nitrogen containing π-conjugated dendrimers N3B6 and N3B3, with peripheral boron atoms and 1,3,5-triaminobenzene moiety as a core, are presented. UV−vis absorption and emission measurements reveal that the opticalproperties of the resulting compounds can be controlled by changing the donor/acceptor ratio: a 1:1 ratio results in a