Pentamethyldiethylene triamine

In addition to neutral five-coordinate aluminum alkyls, rare examples of five-coordinate cationic compounds have also been reported.101 The cationic compound [(PMDETA)AlMe2][Me2AlCl2] (PMDETA = pentamethyldiethylene triamine) (Figure 10(a)) was prepared by the reaction of Me2AlCl with PMDETA in toluene. The NMR showed... 

A mixture consisting of the Step 1 product (0.67 mmol) and CuBr (0.95 mmol) mixed with styrene (95 mmol) was stirred until the polymer dissolved. Pentamethyldiethylene triamine (0.95 mmol) was added, and the mixture was heated for 2 hours at 100°C. After cooling to ambient temperature the viscous polymer was dissolved in 150 ml of THF and then passed through a column of neutral alumina. The solution was concentrated, the residue precipitated in methanol, and the polymer isolated having polydispersity index of 1.1. 

If the reduction of Cp2"UCl2 is made with Na/Hg or Lin-Bu in the presence of donors such as THF, tetramethylethylene diamine (TMEDA), or pentamethyldiethylene triamine (PMDETA), monomeric compounds of the general formula Cp2"U(ju.Cl)2ML are obtained, where for M = Na, L = (THF)2 or TMEDA, and for M = Li, L = (THF)2, TMEDA, or PMDETA. The structures of two of these compounds are shown in Figs. 10 and 11. (Other examples of anionic U(III) organome-tallic compounds can be found in Section V,A,4.)... 

Ni(cyclam)Br2 (cyclam = 1,4,8,11-tetraazacj clotetradecane) [17], or NiBr2(dme) with N,N,N, N, N -pentamethyldiethylene triamine (PMDTA) (dme = dimethoxyethane) [18] have been prepared and used in catalytic amounts in electrocarboxylation. 

Prepare a solution of MM A (9.4 mmol), dimethyl 5-(4-(bromomethyl) benzyloxy) benzene-1,3-dioate (initiator III, 0.187 mmol), copper (I) bromide (0.037 mmol), N,N,N, N",N"-pentamethyldiethylene triamine (PMDETA) (0.0370 mmol) in DMF and keep the reaction mixture in an oil bath at 110 C imder an argon atmosphere. Product recovery is achieved using water. 

Unsaturated carboxylic acid magnesium salts have been obtained catalytically by reductive electrocarboxylation of a number of allenes with a L Ni(II)-complex [L = bpy, dppe, PMDTA (A,A,A W A -pentamethyldiethylene triamine)], as the catalyst, in the presence of a sacrificial magnesium anode [46, 83] (see also Sect. 5.3).However, regioselectivity was moderate. In additimi to a,p-unsaturated acids, the process afforded vinyl acetic acid derivatives, involving carboxylation of a terminal carbon of allene moiety, and di-carboxyUc acids. Catalytic double... 

Using novel asymmetric difunctional initiators containing TEMPO and 2-bromopropanoate or 2-bromo-2-methylpropanoate groups, block copolymers can be prepared via combination of ATRP and STRP [147,148]. For example, asymmetric difunctional initiator, CLI-25 was used in the ATRP of MM A with CuCl/N, N, N , N ,N -pentamethyldiethylene-triamine (PMDETA) as catalyst. The low initiator efficiency (i.e. 0.8) may be related to the side reactions that occur in the initiation step. Subsequently, the TEMPO-terminated PMMA was used as the macroinitiator in the nitroxide-mediated radical polymerization of St at 125 °C. A series of block copolymers, PMMA-6-PSt [147], PrBA-6-PSt [147] and PtBA-6-PMMA-Zi-PSt [148] have been obtained, an example of which is shown in Scheme 3.36. 

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