Photophysical properties of ?-?-conjugated alternating oligothienylene-oligosilylene polymers

Influence of chemical structure of branched and dendritic organosilicon luminophores on their optical and thermal properties

“…First, unsymmetrical organosilicon branched molecule having six donor units and part (phenyl ring) of the acceptor fragment Br-Ph-Si 3 (2T) 2 (2T-Hex) 4 was synthesized via lithiation of 2T-SiMe(2T-Hex) 2 followed by the reaction with Br-Ph-SiMeCl 2 in 78% yield. Second, (PTPTP)Si 6 (2T) 4 (2T-Hex) 8 was prepared by Suzuki crosscoupling reaction between Br-Ph-Si 3 (2T) 2 (2T-Hex) 4 and PinB-TPT-BPin. Purification of the target NOL was made by column chromatography on silica gel to give pure (PTPTP)Si 6 (2T) 4 (2T-Hex) 8 with 32% isolated yield.…”

“…General scheme for the synthesis of a new NOL with four donor units (PTPTP)Si 2 (2T-Hex) 4 and NOL with twelve donor units (PTPTP)Si 6 (2T) 4 (2T-Hex) 8 , is shown in Scheme 1. Preparation of Br-Ph-SiMe(2T-Hex) 2 was described in details before [17].…”

“…A Suzuki coupling reaction between Br-Ph-SiMe(2T-Hex) 2 and PinB-TPT-BPin led to the desired (PTPTP)Si 2 (2T-Hex) 4 in 63% reaction yield (as determined by GPC analysis of the reaction mixture) and 52% isolated yield (after purification by column chromatography) (Scheme 1a). (PTPTP)Si 6 (2T) 4 (2T-Hex) 8 was prepared through a two-step synthesis (Scheme 1b). First, unsymmetrical organosilicon branched molecule having six donor units and part (phenyl ring) of the acceptor fragment Br-Ph-Si 3 (2T) 2 (2T-Hex) 4 was synthesized via lithiation of 2T-SiMe(2T-Hex) 2 followed by the reaction with Br-Ph-SiMeCl 2 in 78% yield.…”

“…A number of linear [8], star-shaped [9][10][11] and dendritic conjugated molecules [12][13][14], containing silicon atoms and showing good luminescent properties are described in the literature. It was shown that usually silicon atoms break the conjugation between the adjacent luminophores covalently bonded to them that can lead to increasing the luminescence efficiency in some highly branched macromolecules [15].…”

“…As a consequence, the aim of this work was the synthesis and systematic investigation of the optical and thermal properties of a series of NOLs based on PTPTP and 2T organic luminophores, having different ratio of the donor to acceptor units -4 :1, 6:1 and 12:1 ( Figure 1). 4 , (PTPTP)Si 2 (2T-Hex) 6 and (PTPTP)Si 6 (2T) 4 (2T-Hex) 8 synthesized and investigated in this work. [17], (2,2'-bithien-5-yl)[bis(5'-hexyl-2,2'-bithien-5-yl)]methylsilane 2T-SiMe(2T-Hex) 2 [19] were prepared as reported before.…”