Star‐Shaped D‐π‐A Molecules Containing a 2,4,6‐Tri(thiophen‐2‐yl)‐1,3,5‐triazine Unit: Synthesis and Two‐Photon Absorption Properties

Abstract

Abstract A series of new star‐shaped donor‐π‐acceptor (D‐π‐A) molecules containing the 2,4,6‐tri(thiophen‐2‐yl)‐1,3,5‐triazine unit were synthesized and characterized. The 1,3,5‐triazine group, as a strong electron‐accepting center, is connected to three electron‐donating end groups through π‐conjugated bridges. As a result of the coexistence of the electron acceptor and donor, these compounds show reversible or quasireversible redox behavior. Through changing the peripheral end group the optical properties can be modified. All compounds exhibit two‐photon absorption activity in the range of 720–880 nm and show large two‐photon absorption cross sections that are closely related to the intramolecular charge transfer and π‐conjugated length of the molecule.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)