Chirally regulated π-conjugated polymers containing platinum (Pt) complex moieties have great potential as chiroptically functional materials. In this study, novel platinum-containing conjugated polymers, poly­(1a-2) and poly­(1b-2), were synthesized by the dehydrochlorination coupling polymerization of dichloro­(4,4′-tert-butyl-2,2′-bipyridyl)­platinum (1a) and dichloro­(4,4′-dinonyl-2,2′-bipyridyl)­platinum (1b) with N-[3,5-bis­(4-ethynylphenylethynyl)­benzoyl]-l-alanine dodecylamide (2), and their chiral secondary structures in solutions were investigated. Poly­(1a-2) exhibited bisignate circular dichroism (CD) signals assignable to the main chain chromophore (300–450 nm) in dimethylformamide (DMF)/MeOH = 50/50 (v/v). The presence of particles of Z-average = 30 nm was confirmed in this solution. These results indicated that poly­(1a-2) formed chirally regulated aggregates. Single-crystal X-ray analysis of the model compound and density functional theory (DFT) calculations were carried out to examine the mode of aggregation of the polymers.

Ring-opening metathesis polymerization (ROMP) of norbornene derivatives is useful for preparing thermally stable and transparent polymeric materials with good moldability. This study deals with ROMP of norbornene monomer 1 bearing...

The functionalization of the chain end of a polymer is gathering increasing attention in the field of synthetic polymer chemistry. The present study is the first example to demonstrate the incorporation of a platinum−acetylide complex at the terminal of a polynorbornene derivative. N-Benzyl-5-norbornene-2-exo,3exo-dicarboxyimide (1) was polymerized with Grubbs 3rdgeneration catalyst (G3). The polymerization was quenched with (Z)-1,4-bis(3-((trimethylsilyl)ethynyl)phenoxy)-2-butene (2) to obtain poly(1)′, followed by the cleavage of trimethylsilyl group and dehydroiodination coupling with trans-bis(tributylphosphine)phenylethynyl iodo platinum (3a) to obtain poly(1a), which was functionalized with a platinum complex at the chain end. Poly(1)′ exhibited no remarkable absorption around 330 nm, while poly(1a) exhibited an intense absorption based on ligand-to-metal chargetransfer transition. Poly(1b) functionalized with a naphthylamide ethynyl platinum complex was synthesized in a similar fashion. The photoluminescene color of a poly(1b) solution in CH 2 Cl 2 changed from green to red with Ar bubbling and rapidly returned to green by ceasing Ar bubbling. A poly(1b)-containing polymethyl methacrylate film exhibited a similar trend, as was observed for the polymer in solution. The weight residues of poly(1a) and poly(1b) at 800 °C were higher than that of poly(1).

The λmax values of platinum-containing poly(phenyleneethynylene)s with aryl groups bonded to P were higher than those with alkyl groups.

Platinum (Pt)-containing novel conjugated polymers, poly(1-2a)− poly(1-2d) having bipyridine ligands were synthesized by the Sonogashira−Hagihara coupling polymerization of [Pt(4,4′-dibromo-2,2′-bipyridine)((R,R)-2,3-bis(tertbutylmethylphosphino)quinoxaline)(trifluoromethanesulfonate) 2 ] (1) coordinated with 4,4′-dibromo-2,2′-bipyridine/(R,R)-2,3-bis(tert-butylmethylphosphino)quinoxaline [(R,R)-QuinoxP*] and 1,4-diethynylbenzene (2a), 1,4-diethynyl-2,5bis(heptyloxy)benzene (2b), 1,4-diethynyl-2,5-bis(2-ethylhexyloxy)benzene (2c), and 1,4-diethynyl-2,5-bis(2-(2-methoxyethoxy)ethoxy)benzene (2d). Poly(1-2d) exhibited circular dichroism signals derived from (R,R)-QuinoxP* and the conjugated main chain around 290 and 440 nm in DMF, respectively. The simulated CD spectroscopic pattern of a low molecular model compound, M1-Pt, agreed well with the observed spectra. The TEM images of poly(1-2d) in the solid state exhibited dispersed patterns with sizes around 10 nm. Concentrated solutions of polymer 1-2d in DMF and CHCl 3 partly exhibited patterns assignable to the formation of lyotropic liquid crystals.