Efficient room temperature catalytic synthesis of alternating conjugated copolymers via C-S bond activation

Abstract

Structural defects in conjugated copolymers are severely detrimental to the optoelectronic properties and the performance of the resulting electronic devices fabricated from them. Therefore, the much-desired precision synthesis of conjugated copolymers with highly regular repeat units is important, but presents a significant challenge to synthetic materials chemists. To this end, aryl sulfides are naturally abundant substances and offer unrealized potential in cross-coupling reactions. Here we report an efficient room temperature polycondensation protocol which implements aryl disulfide C-S activation to produce defect-minimized semiconducting conjugated copolymers with broad scope and applicability. Thus, a broad series of arylstannanes and thioethers are employed via the present protocol to afford copolymers with number-average molecular weights (Mns) of 10.0–45.0 kDa. MALDI and NMR analysis of selected copolymers reveals minimal structural defects. Moreover, the polymer trap density here is smaller and the field effect mobility higher than that in the analogous polymer synthesized through thermal-activation Stille coupling.

Effects of surface acidity on the structure of organometallics supported on oxide surfaces

“…Though the rate limiting step in this reaction is not known, in solution cationic d 0 organometallics react faster in s-bond metathesis reactions than related neutral species, 151 suggesting that d 0 M-H + may accelerate alkane rearrangements. 152 We prepared Ta-H + sites on SAO (Fig. 19(a)) 153 and compared their reactivity to Ta-H supported on SiO 2 , the latter of which are known to catalyze alkane hydrogenolysis reaction.…”

“…Though the rate limiting step in this reaction is not known, in solution cationic d 0 organometallics react faster in σ-bond metathesis reactions than related neutral species, 151 suggesting that d 0 M–H + may accelerate alkane rearrangements. 152…”

An efficient direct arylation polycondensation via C-S bond cleavage

“…Recently, the rst carbonsulfur bond activation based polymerization (CASP) of the aryl thioethers and aryl stannanes were reported for precise synthesis of CPs (Fig. 1b) 33 . However, the toxicity of the tin-reagents obviously hindered the large-scale application.…”

A Random Terpolymer Donor with Similar Monomers Enables 18.28% Efficiency Binary Organic Solar Cells with Well Polymer Batch Reproducibility

“…To overcome this problem, synthesis of terpolymers by selecting the two of three monomers with the same or similar skeletons but different functional groups not only can reduce the disorder of the molecular packing formed by random copolymerization but also can keep the advantages of the random terpolymers on optimization of the optoelectronic property and achievement of a more favorable morphology. − Thus, several conjugated terpolymers based on structure-similar monomers are synthesized, including D–A 1 –D–A 2 type terpolymers PM6–5Si, PF1, and D 1 –A–D 2 –A type terpolymers PL-1, PL-2, PM6-D1, PT2, PM6-SiCl10%, and PM6-Si30, etc. ,− Meanwhile, owing to its planar fused-ring skeleton and self-assembly feature, dithieno­[3′,2’:3,4;2″,3”:5,6]­benzo­[1,2- c ]­[1,2,5]­thiadiazole (DTBT) becomes one of the most popular electron-deficient unit for high-performance polymers. ,− Although some efficient DTBT-based binary copolymers for OSCs have been reported recently, ,− DTBT unit has been less used to synthesize high-performance D–A alternative conjugated terpolymers. Therefore, to enrich the types of conjugated terpolymers and enhance the device performance, − it is very essential to select the strategy of structure-similar skeletons with the different functional groups and precise control of the molar ratios of each unit to synthesize DTBT-based terpolymer with high PCE and well batch reproducibility.…”