79365-81-4Relevant academic research and scientific papers
Universal Suzuki-Miyaura Catalyst-Transfer Polymerization for Precision Synthesis of Strong Donor/Acceptor-Based Conjugated Polymers and Their Sequence Engineering
Choi, Tae-Lim,Chung, Taek Dong,Hwang, Soon-Hyeok,Kim, Hwangseok,Kim, Taehyun,Lee, Jaeho,Park, Hyunwoo,Seo, Daye
, p. 11180 - 11190 (2021)
Catalyst-transfer polymerization has revolutionized the field of polymer synthesis due to its living character, but for a given catalyst system, the polymer scope is rather narrow. Herein we report a highly efficient Suzuki-Miyaura catalyst-transfer polymerization (SCTP) that covers a wide range of monomers from electron-rich (donor, D) to electron-deficient (acceptor, A) (hetero)arenes by rationally designing boronate monomers and using commercially available Buchwald RuPhos and SPhos Pd G3 precatalysts. Initially, we optimized the controlled polymerization of 3,4-propylenedioxythiophene (ProDOT), benzotriazole (BTz), quinoxaline (QX), and 2,3-diphenylquinoxaline (QXPh) by introducing new boronates, such as 4,4,8,8-tetramethyl-1,3,6,2-dioxazaborocane and its N-benzylated derivative, to modulate the reactivity and stability of the monomers. As a result, PProDOT, PBTz, PQX, and PQXPh were prepared with controlled molecular weight and narrow dispersity (C 85%). A detailed investigation of the polymer structures using 1H NMR and MALDI-TOF spectrometry supported the chain-growth mechanism and the high initiation efficiency of the SCTP method. In addition, the use of RuPhos-Pd showing excellent catalyst-transfer ability on both D/A monomers led to unprecedented controlled D-A statistical copolymerization, thereby modulating the HOMO energy level (from -5.11 to -4.80 eV) and band gap energy (from 1.68 to 1.91 eV) of the resulting copolymers. Moreover, to demonstrate the living nature of SCTP, various combinations of D-A and A-A block copolymers (PBTz-b-PProDOT, PQX-b-PProDOT, and PQX-b-PBTz) were successfully prepared by the sequential addition method. Finally, simple but powerful one-shot D-A block copolymerization was achieved by maximizing the rate difference between a fast-propagating pinacol boronate donor and a slow-propagating acceptor to afford well-defined poly(3-hexylthiophene)-b-poly(benzotriazole).
BICYCLIC PHOSPHANES. PART 2. SPONTANEOUS DIMERIZATION OF A CONSTRAINED BICYCLIC PHOSPHANE. THE CRYSTAL AND MOLECULAR STRUCTURE OF A TRICYCLIC COMPOUND CONTAINING THE DIOXADIAZADIPHOSPHECINE RING
Bonningue, Corine,Houalla, Douraid,Wolf, Robert,Jaud, Joel
, p. 773 - 776 (2007/10/02)
The dimerization of 3,3,7,7-tetramethyl-2,8-dioxa-5-aza-1-phosphaIIIbicyclooctane (1) leads to octahydro-2,2,6,6,10,10,14,14-octamehylbis-1,2,3-oxazaphospholo-1,6,3,8,2,7-dioxadiazadiphosphecine (2), a tricyclic compound with sixteen atoms around the periphery.The preparation, identification, and the X-ray structure are described.A pathway for the formation of the dimer is suggested by the trans-position of the two phosphorus ione pairs.
