Diethyl 2,3-dicyano-2,3-diphenylsuccinate Research Articles

Reverse ATRP of Methacrylonitrile with Diethyl 2,3-Dicyano-2,3-Diphenyl Succinate/SmCl3/Lactic Acid

Diethyl 2, 3-dicyano-2, 3-diphenyl succinate (DCDPS) was applied to initiate reverse atom transfer radical polymerization of methacrylonitrile (MAN) in N,N-dimethylformamide (DMF) with SmCl3 and lactic acid (LA) as catalyst and ligand for the first time. The polymerization proceeded in a well-controlled manner as evidenced by kinetic studies. Compared with reverse atom transfer radical polymerization initiated by AIBN, the polymerization initiated by DCDPS not only showed better control of molecular weight, but also provided narrower molecular weight distribution. The slow polymerization rate and the broad polydispersity index were observed using cyclohexanone and toluene instead of DMF as reaction media. There was no apparent variation of the polymerization rate and polydispersity with initial monomer concentration. The block copolymer PMAN-b-PSt was obtained via a conventional ATRP process by using the resulting poly(methacrylonitrile) as macroinitiator.

Reverse ATRP of 4-vinylpyridine with Diethyl 2,3-Dicyano-2,3-Diphenylsuccinate/CuCl 2/5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazamacrocyclotetradecane

Diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS) was applied to initiate reverse atom transfer radical polymerization of 4-vinylpyridine (VP) in 2-propanol with CuCl 2 and 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazamacrocyclotetradecane (Me 6[14]aneN 4) as catalyst and ligand for the first time. First-order kinetics of the polymerization rate with respect to the monomer concentration, linear increase of the molecular weight with monomer conversion and a polydispersity index in the range of 1.15–1.28 were indicatives of controlled radical polymerization. Use of Me 6[14]aneN 4 as the ligand had many advantages over the use of hexamethyl tris[2-(dimethylamino)ethyl]amine (Me 6-TREN) and 2,2′-bipyridine (bpy). A slower polymerization rate and a broad polydispersity index were observed using CuBr 2 instead of CuCl 2 as catalyst. The block copolymer PVP-b-PAN was obtained via a conventional ATRP process in N, N-dimethylformamide (DMF) using the resulting poly (4-vinylpyridine) as macroinitiator.

Reverse ATRP of acrylonitrile with diethyl 2,3-dicyano-2,3-diphenyl succinate/FeCl 3/iminodiacetic acid

The reverse atom transfer radical polymerization (RATRP) technique using FeCl 3/iminodiacetic acid (IMA) complex as a catalyst was applied to the living radical polymerization of acrylonitrile (AN). A hexa-substituted ethane thermal initiator, diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS), was firstly used as the initiator in this iron-based RATRP system. The polymerization in N, N-dimethylformamide not only shows the best control of molecular weight and its distribution but also provides rather rapid reaction rate with the ratio of [AN]:[DCDPS]:[FeCl 3]:[IMA] at 500:1:2:4. The rate of polymerization increases with increasing the polymerization temperature and the apparent activation energy was calculated to be 49.9 kJ mol −1. The polymers obtained were end-functionalized by chlorine atom, and they were used as macroinitiators to proceed the chain extension polymerization in the presence of FeCl 2/IMA catalyst system via a conventional ATRP process. The resultant polyacrylonitrile fibers were obtained with the fineness at 1.16 dtex and the tenacity at 6.01cN dtex −1.

Synthesis of polyacrylonitrile via reverse atom transfer radial polymerization (ATRP) initiated by diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate, FeCl3, and triphenylphosphine

AbstractThe reverse atom transfer radical polymerization (RATRP) technique using FeCl3/triphenyl‐phosphine (PPh3) complex as a catalyst was applied to the living radical polymerization of acrylonitrile (AN). A hexa‐substituted ethane thermal iniferter, diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS), was first used as the initiator in this iron‐based RATRP initiation system. A FeCl3 to PPh3 ratio of 1:3 not only gives the best control of molecular weight and its distribution but also provides a rather rapid reaction rate. The rate of polymerization increases with increasing the polymerization temperature and the apparent activation energy was calculated to be 54.9 kJ mol−1. Because the polymers obtained were end‐functionalized by chlorine atoms, they were used as macro‐initiators to proceed the chain extension polymerization in the presence of an FeCl2/PPh3 catalyst system via a conventional ATRP process. Copyright © 2005 Society of Chemical Industry

A copper‐based reverse atom‐transfer radical polymerization process for the living radical polymerization of polyacrylonitrile

AbstractThe reverse atom‐transfer radical polymerization (RATRP) technique using CuCl2/2,2′‐bipyridine (bipy) complex as a catalyst was applied to the living radical polymerization of acrylonitrile (AN). A hexasubstituted ethane thermal iniferter, diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS), was firstly used as the initiator in this copper‐based RATRP initiation system. A CuCl2 to bipy ratio of 0.5 not only gives the best control of molecular weight and its distribution, but also provides rather rapid reaction rate. The rate of polymerization increases with increasing the polymerization temperature, and the apparent activation energy was calculated to be 57.4 kJ mol−1. Because the polymers obtained were end‐functionalized by chlorine atoms, they were used as macroinitiators to proceed the chain extension polymerization in the presence of CuCl/bipy catalyst system via a conventional ATRP process. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 226–231, 2006

Preparation of vinyl polymers bearing photo‐labile diethylthiocarbamoylthiyl (S2CNEt2) groups via ATRP

AbstractDirect synthesis of vinyl polymers functionalized with photo‐labile diethylthiocarbamoylthiyl (S2CNEt2) groups was reviewed via three living polymerization procedures: normal atom‐transfer radical polymerization (ATRP), reverse ATRP and photo ATRP. The S2CNEt2 group was transferred by mediating the dormant–active species equilibrium in the course of polymerization and eventually ω‐terminating the resulting polymer chain. ATRP of methyl methacrylate (MMA) was successfully performed with a p‐toluenesulfonyl chloride/Cu(S2CNEt2)/2,2′‐bipyridine(bpy) or benzoyl peroxide (BPO)/Cu(S2CNEt2)/bpy initiation system. The oxidized complex, Cu(S2CNEt2)Cl/bpy, catalyzed the reverse ATRP of vinyl monomers initiated with BPO or 2,2′‐azobisisobutyronitrile (AIBN), producing tailor‐made polymers with ω‐S2CNEt2 groups and a narrow molecular‐weight distribution. Without external ligands, the living polymerization of vinyl monomers was achieved under the thermal initiation of diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS) in conjunction with Fe(S2CNEt2)3 catalyst. Photo ATRP of MMA and styrene was first realized in the presence of 2,2‐dimethoxy‐2‐phenylacetophenone (DMPA)/Fe(S2CNEt2)3 under UV irradiation at ambient temperature. Copyright © 2004 Society of Chemical Industry

Reverse atom transfer radical polymerization of vinyl monomers with Fe[SC(S)NEt2]3 alone as the catalyst

AbstractThe living radical polymerization of methyl methacrylate and styrene was successfully carried out with diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS)/ferric tri(diethyldithiocarbamate) as a novel reverse atom transfer radical polymerization initiation system in which DCDPS was a hexa‐substituted ethane‐type thermal iniferter, DC was a diethyldithiocarbamate group, and no additional ligands such as nitrogen‐ or phosphine‐based compounds were required. The bulk polymerization of methyl methacrylate was carried out at 95 °C, and that of styrene was carried out at 120 °C. Poly(methyl methacrylate) and polystyrene (PSt) with high molecular weights and quite narrow molecular weight distributions (as low as 1.09 for PSt) were obtained. 1H NMR spectroscopy revealed the presence of an α‐(carbethoxycyanophenyl)methyl group from the initiator and an ω‐DC group from the catalyst in the obtained polymers. Various chain‐extension reactions under UV light or thermal treatments were successfully conducted to prove the presence and efficient reinitiating of the ω‐DC group. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3464–3473, 2001

A copper‐based reverse ATRP process for the living radical polymerization of methyl methacrylate

AbstractThe reverse atom transfer radical polymerization (RATRP) technique using CuCl2/bipyridine (bipy) complex as a catalyst was applied to the living radical polymerization of methyl methacrylate (MMA). A hexa‐substituted ethane thermal iniferter, diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS), was used as the initiator in this copper‐based reverse ATRP initiation system. The reversible dissociation nature of DCDPS gives a more suitable amount of primary radical than formerly used conventional initiators, such as AIBN. High molecular weight and narrow molecular weight distribution (Mw/Mn ≈ 1.20) of the resulting PMMA was obtained in bulk and in solution polymerization at 85°C. End‐group analysis result by 1H‐NMR spectroscopy shows that the polymer obtained is ω‐functionalized by a chlorine group, which can be used as macroinitiator for chain extension and block copolymerization with a conventional ATRP catalyst. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2237–2245, 2001

Radical polymerization of styrene by a hexa‐substituted‐ethane type thermal iniferter

AbstractThe bulk polymerization of styrene (St) initiated with a hexa‐substituted‐ethane type initiator, diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS), was investigated. It was found that DCDPS served as a thermal iniferter for polymerization of St and the polymerization had some characteristics in common with living radical polymerization, ie, both the yield and the molecular weight of the resulting polymers increased with increasing reaction time. The resultant polystyrene can act as a macroinitiator for chain‐extension polymerization of St or for radical polymerization of methyl methacrylate to give a block copolymer.© 2001 Society of Chemical Industry

Living/controlled radical polymerization of methyl methacrylate by reverse ATRP with DCDPS/FeCl3/PPh3 initiating system

Living/controlled radical polymerization of methyl methacrylate (MMA) was investigated using a new initiating system, i.e. DCDPS/FeCl3/PPh3, in which diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS) is a hexa-substituted ethane thermal iniferter. The polymerization mechanism belongs to a reverse ATRP process. The polymerization was closely controlled in bulk and in solution at quite low temperature such as 75 or 60°C. The molecular weights of so-obtained PMMA were high and polydispersities were quite narrow (Mw/Mn=1.20–1.31). End group analysis result using 1H NMR spectroscopy shows that the polymer obtained is ω-functionalized by a chlorine atom. With the Cl atom at the chain end, PMMA obtained could be used as macroinitiator to proceed chain-extension reaction with MMA and block copolymerization reaction with styrene in the presence of CuCl/bipy catalyst via a conventional ATRP process.

Living/controlled radical polymerization of styrene with a new initiating system: DCDPS/FeCl3/PPh3

The living/controlled radical polymerization of styrene was investigated with a new initiating system, DCDPS/FeCl3/PPh3, in which diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS) was a hexa-substituted ethane thermal iniferter. The polymerization mechanism belonged to a reverse atom transfer radical polymerization (ATRP) process. The polymerization was controlled closely in bulk (at 100 °C) or in solution (at 110 °C) with a high molecular weight and quite narrow polydispersity (Mw/Mn = 1.18 ∼ 1.28). End-group analysis results by 1H NMR spectroscopy showed that the polymer was ω-functionalized by a chlorine atom, which also was confirmed by the result of a chain-extension reaction in the presence of a FeCl2/PPh3 or CuCl/bipy (2,2′-bipyridine) catalyst via a conventional ATRP process. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 101–107, 2000

?Living? radical polymerization of methyl methacrylate with diethyl 2,3-dicyano-2,3-diphenylsuccinate as a thermal iniferter

The bulk polymerization of methyl methacrylate (MMA) initiated with diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS) was studied. This polymerization showed some “living” characteristics; that is, both the yield and the molecular weight of the resulting polymers increased with reaction time, and the resultant polymer can be extended by adding MMA. The molecular weight distribution of PMMA obtained at high conversion is fairly narrow (Mw/Mn = 1.24≈1.34). It was confirmed that DCDPS can serve as a thermal iniferter for MMA polymerization by a “living” radical mechanism. Furthermore, the PMMA obtained can act as a macroinitiator for radical polymerization of styrene (St) to give a block copolymer. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4610–4615, 1999