Synthesis and properties of 5,7-disubstituted 5,7-dihydropyrido[2,3- b:6,5- b′]diindoles.

A new and efficient two-step procedure for the preparation of 5,7-disubstituted 5,7-dihydropyrido[2,3- b:6,5- b′]diindoles, containing aryl-, benzyl- as well as alkyl-substituents has been developed. This methodology consists of a chemo-selective double Suzuki-Miyaura cross-coupling reaction followed by a fourfold Buchwald-Hartwig amination reaction. UV/VIS absorption and fluorescence measurements have been carried out for a selected series of compounds. The results are summarized and compared with those of the isomeric 5,7-disubstituted 5-7-dihydropyrido[3,2- b:5,6- b′]diindoles. [ABSTRACT FROM AUTHOR]