Nucleophylic substitution

These compounds were also reduced in the presence of the quinone electron carrier, juglone, and it is postulated that the actual electron carrier is a mercaptoju-glone formed by the reaction of H2S with the quinone. This introduces an additional complicating factor in that these HS compounds can act as nucleophiles undergoing a nucleophylic substitution reaction with alkyl hahdes (see Hydrolysis, Chapter 8) and the data suggest that both reactions are occurring. 

Fuentes s group reported the synthesis of polyhydroxy piperidines (Scheme 8) starting from partially protected P-D-ribopyranosylenamine 22 [58]. Thus, mesylation on the free hydroxyl group led to the corresponding 5-mesyloxy and 5-chloro derivatives 23 and 24, the latter obtained by nucleophylic substitution on the mesyloxy group when longer reaction times and more concentrated solutions were used. 

In connection with big perspectiveness of polyarylesterketones, the examining of the most popular methods for their production was of interest. The literature data analysis shows that the synthesis of aromatic polyes-terketones can be done by the acylation on Friedel-Ciafts reaction or by reaction of nucleophylic substitution of activated dihalogen-containing aromatic compounds and bisphenolates of alkali metals [224,229]. 

The aromatic polyketones, containing 1,4-naphthalene links were produced in Ref. [363] by the reaction of nucleophylic substitution of l-chlor-4-(4 -chlorbenzoyl)naphthalene with 1) 1,4-hydroquinone, 2) 4,4 -isopropylidenediphenol, 3) phenolphthalein, 4) 4-(4 -hydroxyphenyl) (2H)-phthalasine-l-one, respectively. All polymers are amorphous and dissipate in some organic solvents. The polymers have good thermo-stability and the high glassing temperatures. 

The polyarylenesterketones have been produced by the reaction of nucleophylic substitution of 4,4 -difluorobenzophenone with hydroqui-none [374]. The synthesis is held in sulfolane in the presence of anhydrous the K2CO3. The increasing content of methylhydroquinone links in... 

The random copolymers of polyarylesterketones were produced by means of nucleophylic substitution [385] the basis of bisphenol A and carding bisphenols (in particular, phenolphthalein). 

The high-molecular block-copolyarylenesterketones have been S5m-thesized on the basis of 4,4 -difluorobenzophenone and number of bisphe-nols by means of reaction of nucleophylic substitution of activated aryl-halogenide in dimethylacetamide (in the presence of potassium carbonate) [394, 395]. It has been identified the cutback of molecular weight of polymer when using bisphenolate of 4,4 -(isopropylidene)bisphenol. 

Difluoro-2,4,6-triazidopyridine (202) has been synthesized by reaction of nucleophylic substitution from pentafluoropyridine (144) and sodium azide [128, 129]. The 3,5-difluoro-2,4,6-tiinitren (203) has been obtained further from this compound and investigated by IR-spectroscopy [128,129] (Scheme 63). 

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