Phase Transfer Catalyzed Polycondensation of α, α′-Dichloro-p-xylene with 2,2-Bis(4-hydroxyphenyl)propane II. Some Aspects of Phase Transfer Catalyzed Polycondensation Reaction in the Tetrahydrofuran-Dimethyl Sulfoxide/ Aqueous Sodium Hydroxide System

AbstractTo increase the solubility and produce cationic or ampholytic polymers as beater additives in papermaking from native hemicelluloses, quaternization of hemicelluloses were performed by reacting hemicelluloses with 3-chloro-2- hydroxypropyltrimethylammonium chloride (CHMAC) and preferably with 2,3- epoxypropyltrimethylammonium chloride (ETA) in aqueous sodium hydroxide, homogenously in dimethyl sulfoxide (DMSO), and completely heterogeneously in ethanol/water, respectively. The extent of modification was measured by degree of substitution (DS), and its value of up to 0.55 can be controlled by adjusting the molar ratio of reagent to hydroxyl functionality in hemicelluloses and the concentration of sodium hydroxide. The characterization of hemicellulosic derivatives was performed by elemental analysis, GPC, FT-IR and 13C NMR spectroscopy as well as thermal analysis. It was found that hemicellulosic polymer was significantly degraded in aqueous sodium hydroxide solution compared with in dimethyl sulfoxide and in ethanol/water systems under the conditions given. The thermal stability of modified hemicelluloses decreased after chemical modification, corresponding to the decreasing Mw of hemicelluloses derivatives.

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ChemInform Abstract: Phase-Transfer-Catalyzed O-Acetylation of Phenol with Acetyl Chloride in the Presence of Aqueous Sodium Hydroxide.

ChemInform ◽

10.1002/chin.199344135 ◽

2010 ◽

Vol 24 (44) ◽

pp. no-no

Author(s):

I. HASHIMOTO ◽

T. HIGASHI

Keyword(s):

Sodium Hydroxide ◽

Acetyl Chloride ◽

Phase Transfer ◽

Aqueous Sodium Hydroxide ◽

Aqueous Sodium

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Extraction of cos dissolved in n-heptane into aqueous sodium hydroxide: Phase transfer catalysis

Chemical Engineering Science ◽

10.1016/0009-2509(83)80144-4 ◽

1983 ◽

Vol 38 (1) ◽

pp. 141-145 ◽

Cited By ~ 3

Author(s):

R.R. Bhave ◽

M.M. Sharma

Keyword(s):

Sodium Hydroxide ◽

Phase Transfer Catalysis ◽

Phase Transfer ◽

Aqueous Sodium Hydroxide ◽

Aqueous Sodium ◽

Hydroxide Phase

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Tricyclic psychotropic agents containing two chalcogen atoms in the central ring: Synthesis of 6-(aminoalkyl) derivatives of 6H-dibenz[b,e]-1,4-oxathiepin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19821367 ◽

1982 ◽

Vol 47 (5) ◽

pp. 1367-1381 ◽

Cited By ~ 2

Author(s):

Karel Šindelář ◽

Jiří Holubek ◽

Emil Svátek ◽

Miroslav Ryska ◽

Antonín Dlabač ◽

...

Keyword(s):

Dimethyl Sulfoxide ◽

Sodium Hydroxide ◽

Benzyl Bromide ◽

Sodium Hydride ◽

Aqueous Sodium Hydroxide ◽

Aqueous Sodium ◽

Psychotropic Agents ◽

Triethylbenzylammonium Chloride ◽

Boron Tribromide ◽

Derivatives Of

Heating of 2-(2-hydroxyphenylthio)benzoic acid (XX) with acetic anhydride gave dibenz[b,e]-1,4-oxathiepin-6-one (XXII). Demethylation of 2-(2-methoxyphenylthio)benzyl bromide (XI) with boron tribromide and the following treatment with aqueous sodium hydroxide in dimethyl sulfoxide afforded 6H-dibenz[b,e]-1,4-oxathiepin (I) which was halogenated with chlorine or N-bromosuccinimide only to the undesirable 2-halogeno derivatives II and III. A reaction of 2-(2-methoxyphenylthio)benzaldehyde (XII) with chloroform and 50% aqueous sodium hydroxide in the presence of triethylbenzylammonium chloride led to the α-chloro acid XIX whose demethylation with boron tribromide and the following cyclization with sodium hydroxide in dimethyl sulfoxide gave a mixture with prevailing 6H-dibenz[b,e]-1,4-oxathiepin-6-carboxylic acid (IV). Amino alcohols XXV-XXVIII were obtained by reactions of 2-(2-fluorophenylthio)benzaldehyde (XXIV) with the corresponding Grignard reagents and the products were cyclized with sodium hydride in dimethylformamide to the title compounds V-VIII. While compounds V and VI showed antireserpine effects and can be considered as potential antidepresants, compound VIII has a strong central depressant activity, brings about ataxia, hypothermia and potentiates the cataleptic action of neuroleptics (properties of a tranquillizer).

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