PMDETA

Certain multidentate ligands also provide for better solubility. Cu1 complexes formed with tctramcthylcthylcncdiaminc (TMEDA), N,N,N ,N ,N -pentamethyldiethylenetriamine (PMDETA, 140) and 1,1,4,7,10,10-hcxamethyltricthylcnctctraminc (HMTETA, 144) and Mc6TREN (145) have been found effective.311 Transfer to ligand during MMA polymerization has been reported as a side reaction when PMDETA is used. 12 313... 

Lewis acids (dicthylaluminum chloride, ethyl aluminum scsquichloridc) have been used in conjunction with ATRP to provide greater alternating tendency in S-MMA copolytnerization.519 However, poor control was obtained because of interaction between the catalyst (CuCI/dNbpy) and the Lewis acid. Better results were obtained by RAFT polymerization/10 Copper catalysts, in particular Cu(lI)Br/PMDETA, have been shown to coordinate monomer but this has negligible influence on the outcome of copolymerization/6 ... 

In the presence of N,N,N, N",N"-pentamethyldiethylenetriamine ( = PMDETA), monomeric lithium complexes of bulky formamidinate ligands can be isolated. The compounds (Scheme 12) comprise a Li(PMDETA) center coordinated by a bulky formamidinate in either the E-syn- or E-anti-isomeric form. Two of the structures display coordination of the pendant amidinate imine, and can therefore be considered the first examples of if. r -C = N,N metal amidinate coordination. ... 

The zinc tetrasulfido complex ZnS4(PMDETA) (PMDETA=pen-tamethyldiethylenetriamine) reacts with alkynes and CS2 to give the dithiolene complexes ZnS2C2(C02Me)2(PMDETA) and ZnS3CS(PMDETA), respec-... 

Fig. 5. Mark-Houwink plots (a) and RI signals (b) for polymers obtained by SCVCP of t-BuA with the inimer 1 CuBr/PMDETA at 60°C (O) and 100°C (A) CuBr/Bipy at 60°C ( ) and 100 °C (A). The viscosity result for a linear Pf-BuA (—) is given for comparison. (Reproduced with permission from [31], Copyright 2001 American Chemical Society.)...

The bifunctional initiator 4-hydroxy-bulyl-2-bromoisobulyralc, HBBIB, promoted the ATRP of styrene as well as the cationic ring opening polymerization of THF [134], In the presence of Cu/CuBr2/PMDETA styrene was polymerized through the bromoisobutyrate function of HBBIB, to give PS chains end-functionalized with hydroxyl groups, PS-OH. The in situ... 

The same heterobifunctional initiator, 2-phenyl-2-[(2,2,6,6-tetramethy-piperidino)oxy] ethyl 2-bromo-2-methyl propanoate, was employed for the synthesis of PMMA-fo-PfBuA-fo-PS triblock terpolymers via the combination of ATRP and NMP [136]. Styrene was initially polymerized through the alkoxyamine function in bulk at 125 °C, leading to PS chains with bromine end groups. Subsequent addition of fBuA in the presence of CuBr/PMDETA provided the PS-fr-PfBuA diblock. Further addition of CuCl, to achieve halogen exchange and MMA yielded the desired triblock copolymer with... 

Double hydrophilic star-block (PEO-fo-PAA)3 copolymers were prepared by a combination of anionic and ATRP of EO and fBuA [150]. Three-arm PEO stars, with terminal - OH groups were prepared by anionic polymerization, using l,l,l-tris(hydroxymethyl)ethane, activated with DPMK as a trifunctional initiator. The hydroxyl functions were subsequently transformed to three bromo-ester groups, which were utilized to initiate the polymerization of f-butyl acrylate by ATRP in the presence of CuBr/PMDETA. Subsequent hydrolysis of the f-butyl groups yielded the desired products (Scheme 74). 

We were recently able to isolate and structurally characterize a series of [CuI(PMDETA)(7i-M][BPh4] complexes (M = styrene, methyl acrylate, methyl methacrylate, and 1-octene) [110,111]. Molecular structures of [Cu PMDETA) (71-methyl acrylate)] [BPhJ and [CuI(PMDETA)(7i-styrene)][BPh4] are shown in Fig. 5. In all complexes, PMDETA acted as a tridentate ligand, while the... 

Substituted terpyridine, 4,4, 4"-tris(5-nonyl)-2,2 <5, 2"-terpyridine (tNtpy), is a planar tridentate ligand that was successfully used in homogeneous ATRP of methyl acrylate and styrene [79]. Polymerization of both monomers was controlled and the resulting polymers had relatively low polydispersities (MJMn < 1.2). Similarly to PMDETA, the typical ligand to copper halide ratio used in the polymerization was 1 1. Terpyridine and its derivatives are expected to form tetra-coordinated complexes with copper in which the fourth coordination sphere is occupied by a monodentate ligand (Br-, Cl , solvent, monomer, etc.). Although,... 

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