Alkylated polyethyleneimine

The oxidation of methyl phenyl sulfide using fresh PWAA gave methyl phenyl sulfone in 97% yield. In the repeated use of recovered catalyst, the yields of sulfone in runs 2 to 5 ranged from 82 to 88%. The activities of recovered catalysts were somewhat reduced. The deactivation may be caused by catalyst pulverization or degradation of the PW12O403- species. While the reusability and stability of the catalyst should be improved, this concept would be useful for the creation of sophisticated solid catalysts. After Ikegami s reports, Neumann and coworkers [140] applied this strategy to the development of alkylated polyethyleneimine/POM synzymes. 

G. A. Gainanova, E. P. Zhil tsova, L. A. Kndryavtseva, S. S. Lukashenko, A. P. Timosheva, I. R. Knyazeva, A. R. Burilov, A. I. Konovalov, Complex formation and self-association in alkylated polyethyleneimine-calix[4]iesorcinarene-chloroform system, Russ. J. Gen. Chem.,... 

Scheme 9.16 Aqueous biphasic reactions mediated by alkylated polyethyleneimine.

As a consequence of showing that alkylated polyethyleneimines can facilitate aqueous biphasic catalysis, we extended the concept by the preparation of a cross-linked polyethyleneimine assembly that encapsulated a polyoxometalate catalyst, which resulted in the Upophiloselective oxidation of secondary alcohols (Scheme 9.17) [152]. Thus, even though reactions were carried out in water, competitive oxidation of a more hydrophobic alcohol in the presence of a hydrophilic alcohol significantly favored the former. The lipophiloselectivity was proportional to the relative partition coefficient of the substrates. 

Used industrially to cross-link hydroxylic polymers, polyethyleneimine. Possesses some carcinogenic properties. Polyethyleneimine is a hygroscopic liquid used in paper manufacture to confer wet strength and in textiles, alkylated derivatives also form useful polymers. 

Although polyethyleneimine possesses moderate catalytic effects on several hydrolysis reactions, the polymer modified with long alkyl chains show much enhanced reactivity toward hydrophobic substrates. Remarkable catalytic effects were observed in the hydrolysis of phenyl esters and a sulfate ester catalyzed by the methylene-imidazole-modified polymer. These results were explained as arising from the hi y branched, compact stmcture of the polyethyleneimine derivative. Klotz called the imidazole-containing polyethyleneimine synzyme (s)mthetic enzyme), on the basis of its stmctural characteristics and catalytic activity which are comparable to hydrolytic enzymes. 

Linear 2. See Sodium metaphosphate Linear alcohol C13-15. See C13-15 alcohols Linear CIO alpha olefin. See Decene-1 Linear Cl6 alpha olefin. See Hexadecene-1 Linear CIS alpha olefin. See Octadecene-1 Linear C20 alpha olefin. See Eicosene-1 Linear (C12 and C14) alkyl alcohols, ethoxylated. SeeC12-14 pareth Linear polyethyleneimine. See Polyethylene imine... 

Alkyl-substituted polyethyleneimines show maximum activity in catalysing the hydrolysis of 4-nitrophenyl esters when both the substrate and the catalyst contain long-chain alkyl groups. ... 

Reaction with O-alkylated nylon Glutaraldehyde-crosslinked on to a nylon-polyethyleneimine co-polymer Adsorption on to the inner surface of nylon tubing followed by glutaraldehyde crosslinking... 

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