Experimental Evidence for the Quasi-“Living” Nature of the Grignard Metathesis Method for the Synthesis of Regioregular Poly(3-alkylthiophenes)
نویسندگان
چکیده
The Grignard metathesis (GRIM) polymerization of 3-alkylthiophenes proceeds by a quasi“living” chain growth mechanism, not by a step growth process. Kinetic studies of the Grignard metathesis polymerization of 2,5-dibromo-3-alkylthiophenes showed that the molecular weight of poly(3-alkylthiophenes) is a function of the molar ratio of the monomer to nickel initiator, and conducting polymers with predetermined molecular weights and relatively narrow molecular weight distributions (PDIs ) 1.2-1.5) can be made. Sequential monomer addition resulted in new block copolymers containing different poly(3-alkylthiophene) segments.
منابع مشابه
Regioregular, Head-to-Tail Coupled Poly(3-alkylthiophenes) Made Easy by the GRIM Method: Investigation of the Reaction and the Origin of Regioselectivity
An investigation of the new synthetic method to synthesize regioregular, head-to-tail coupled poly(3-alkylthiophenes) using magnesium-halogen exchange (Grignard metathesis) called the GRIM method is described. Treatment of 2,5-dibromo-3-alkylthiophenes with a variety of alkyl and vinyl Grignard reagents resulted in two metalated, regiochemical isomers, namely, 2-bromo-3-alkyl-5-bromomagnesiothi...
متن کاملControl of End-groups of Regioregular Poly(3- Alkylthiophenes) Using Grignard Metathesis
Introduction Poly-3-alkylthiophenes (PATs) constitute an important group of conjugated polymers due to their good solubility, environmental stability, and conductivity. They find potential applications in electronic, photonic and sensor materials and devices. Control over the regiochemistry of poly(3alkylthiophene) has been efficiently achieved by Kumada coupling of either organomagnesium or or...
متن کاملA Simple Method to Prepare Head-to-Tail Coupled, Regioregular Poly(3-alkylthiophenes) Using Grignard Metathesis
± [1] S. Chandrasekhar, Liquid Crystals, Cambridge University Press, Cambridge 1992. [2] G. Blasse, G. J. Dirksen, A. Meijerink, J. F. Van der Pol, E. Neeleman, W. Drenth, Chem. Phys. Lett. 1989, 154, 420. [3] D. Markovitsi, I. Lecuyer, P. Lianos, J. Malthte, J. Chem. Soc., Faraday Trans. 1991, 87, 1785. [4] D. Markovitsi, F. Rigaut, M. Mouallem, J. Malthte, Chem. Phys. Lett. 1987, 135, 236. ...
متن کاملSynthesis of regiospecific poly(3-substituted-thiophenes) using Ni-diimine-initiated cross-coupling polymerization
Introduction Polythiophenes (PTs) continue to be one of the most versatile and extensively studied conjugated polymer systems due to their exceptional spectroscopic and electronic properties, and the ease of synthesis of PTs derivatives. Practical and potential applications of PT derivatives include rechargeable battery, electrochromic devices (ECDs) (e.g., poly(alkylenedioxythiophene) [PXDOT])...
متن کاملRegioregular poly(3-alkylthiophene) conducting block copolymers
Regioregular poly(3-alkylthiophenes) (PATs) represent an important class of polymers that are environmentally stable and display high electrical conductivity. Despite their excellent electrical properties, PATs do not exhibit very good mechanical and processing properties. This issue is addressed here by integrating poly(3-alkylthiophene) in copolymer structures with various polymer blocks that...
متن کامل