Solid Liquid Phase Transfer Catalyst Research Articles

The Investigation of the Alkylation Reactions of Hydroxy and En‐Oximes with Some Halohydrins and Epoxides

Suitable glycol ethers (3a–d, 4a–d) and halohydrine compounds (11a–c) were synthesized in good yield by the alkylation reactions of the oximes, having hydroxy and double bond in its structure, with mono‐ and dihalogenhydrines in the medium of basic and solid–liquid phase transfer catalyst. A series of aminoalcohols were synthesized from these compounds obtained (16a, 17b, 18b).

Synthesis and competency of a tartrate-derived dicationic solid–liquid phase-transfer catalyst

A new asymmetric phase-transfer catalyst is described, along with a new, flexible synthetic scheme using a tartaric acid chloride. Alkylations and Michael reactions on a glycine imino ester show the new catalyst to be an effective phase-transfer catalyst with limited enantioselectivity.

Silicon polypodands: a new class of efficient solid–liquid phase-transfer catalysts

Silicon polypodands 1– 7 were found to be powerful complexing agents of alkali metal salts, even in low polarity media (chlorobenzene) and hence very efficient phase-transfer catalysts. Their catalytic activity was measured in typical anion-promoted reactions under solid–liquid phase-transfer catalysis (SL-PTC) conditions. It is mainly determined by the complexing ability of the ligand, increasing with the number of silicon atoms and binding sites. Comparison with traditional phase-transfer catalysts showed that these polypodands are better catalysts not only than open-chain PEG400Me 2 and TRIDENT, but even than more sophisticated macrocyclic polyethers such as DCH18C6.

Quaternized Amino Functionalized Cross‐Linked Polyacrylamide as a New Solid—Liquid Phase Transfer Catalyst in Reduction of Carbonyl Compounds with NaBH4.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Silicon polypodands: powerful metal cation complexing agents and solid–liquid phase-transfer catalysts of new generation

Silicon polypodands 5– 7 are found to be powerful complexing agents of alkali metal salts in low polarity solvents and very efficient catalysts in anion-promoted reactions under solid–liquid PTC conditions. The catalytic activity is comparable with that of the cyclic polyether PHDB18C6 8 .

Quaternized amino functionalized cross-linked polyacrylamide as a new solid–liquid phase transfer catalyst in reduction of carbonyl compounds with NaBH 4

Poly[ N-(2-aminoethyl)acrylamido]trimethyl ammonium chloride resin was developed as a new polymeric phase transfer catalyst. This quaternized polyacrylamide catalyzed the chemoselective reduction of aldehydes and ketones by NaBH 4 to give corresponding alcohols in high yields under mild conditions.

A Facile Synthesis of Substituted N-Benzoylthiourea

One pot reaction of benzoyl isothiocyanate and Tris(hydroxy- methyl)aminomethane (Tris) at room temperature with polyethylene glycol-400 (PEG-400) as solid–liquid phase-transfer catalyst produced substituted N-benzoylthioureas with high yield. A reasonable pathway for their formation has been suggested.

Synthesis of thiocyanohydrins from epoxides using quaternized amino functionalized cross-linked polyacrylamide as a new solid–liquid phase-transfer catalyst

Poly[ N-(2-aminoethyl)acrylamido]trimethyl ammonium chloride resin was developed as a new polymeric phase-transfer catalyst. This quaternized polyacrylamide catalyzed the regioselective ring opening of epoxides by thiocyanate ion to give thiocyanohydrins in high yields under mild conditions.

A Novel Microwave-Activated Sonogashira Coupling Reaction and Cleavage using Polyethylene Glycol as Phase-Transfer Catalyst and Polymer Support

Under microwave-activation polyethylene glycol bound 4-iodobenzoic acid could be readily reacted with various terminal alkynes in excellent yields and purity using polyethylene glycol (PEG) as a solid-liquid phase-transfer catalyst and polymer support; the cleavage could be dramatically accelerated under microwave activation.

Synthesis of halohydrins from epoxides using quaternized amino functionalized cross-linked polyacrylamide as a new solid–liquid phase transfer catalyst

Poly[ N-(2-aminoethyl)acrylamido]trimethyl ammonium halide resin was developed as new solid–liquid phase transfer catalyst. This quaternized polyacrylamide-catalyzed regioselective ring opening of epoxide by halides (F, Cl, Br, I), to give halohydrins in high yield under mild conditions.

ChemInform Abstract: Etherification of Phenols Catalyzed by Solid‐Liquid Phase Transfer Catalyst PEG400 Without Solvent.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Etherification of Phenols Catalysed by Solid-Liquid Phase Transfer Catalyst PEG400 without Solvent

Aromatic ethers were synthesised in excellent yields(above 86 %) and purity by the etherification of phenols with dimethyl sulfate or alkyl halides, catalysed by phase transfer catalyst PEG400 under solvent-free conditions, and the effects of some key reaction conditions were also studied.

Studies on Glycosides XXI. Solid-Liquid Phase Transfer Catalyzed Reaction of Tetra-O-acetylglycopyranosyl Bromide with Active Methylene Compounds

2,3,4,6-Tetra-O-acetylglycopyranosyl bromide was reacted with active methylene compounds under solid-liquid phase-transfer catalyst conditions, involving anhydrous potassium phosphate as base and TBAB as catalyst in acetonitrile at room temperature, to give the corresponding tetra-O-acetylglycoside 2 in moderate yields.

Amphiphilic Graft Copolymers as Phase-Transfer Catalysts in a Solid-Liquid System

Abstract Amphiphilic graft copolymers consisting of a hydrophobic backbone and poly(oxyethylene) (PEO) side chains were employed as solidliquid phase-transfer catalysts (PTC) in the substitution of octylbromide by solid potassium phenoxide in toluene. A wide variety of structures were synthesized via ester substitution of poly(phthalimidoacrylate) (PPIA) or poly(phthalimidoacrylate-co-styrene) [poly(PIA-co-St)] with amino-functionalized methoxy-PEO (MPEO-NH2). The phase-transfer catalytic activity (PTA) of these soluble graft copolymers was studied as a function of the structure of the backbone, the length of the side chains, and the graft density. The graft copolymers of a high degree of grafting showed PTA higher than that of parent PEOs. GPC was used to study the behavior of the graft copolymers in toluene at 90°C. It is believed that the phase-transfer reaction is accelerated in the PEO microphase.

Triisopropylsilanol: A new type of phase transfer catalyst for dehydrohalogenation

A new solid-liquid phase transfer catalyst, trisopropylsilanol (TIPSOH), has been developed which, through the silanol/silanoate system, allows KOH to quantitatively convert even primary alkyl halides to alkenes avoiding both ether and alcohol by-products. Its potential application in the detoxification of mustard gas analogues and environmental pollutants has been demonstrated.

Solvents as phase-transfer catalysts in reactions initiated by solid bases

For reactions initiated by solid bases (e.g. potassium hydroxide, sodium hydroxide, potassium carbonate), solvents (e.g. water, ButOH, polyethylene glycol, MeCN, Me2SO) may act as solid-liquid phase transfer catalysts (e.g. for C–H, N–H or O–H alkylation by alkyl halides, or epoxidation by sulfonium or sulfoxonium salts).

Synthesis and catalytic activity of a new class of cyclophosphazenic polypodands

AbstractA new class of solid‐liquid phase‐transfer catalysts (SL‐PTC) has been prepared by the reaction of octachlo‐rocyclotetraphosphazatetraene and polyethylene glycol monoalkyl ether. These polypodands are found to be powerful metal cation complexing agents and very efficient catalysts in anion promoted reactions (e.g. nucleophilic substitution and reduction reactions).

The Synthesis of a Chiral Hexaphenyl-18-crown-6 Derivative

The stereospecific synthesis of (2R,3R,8R,9R,14R,15R)-2,3,8,9,14, 15-hexaphenyl-1,4,7,10,13,16-hexaoxacyclooctadedecane [(R,R,R, R,R,R)-12] from (R,R)-hydrobenzoin [(R,R)-1] is reported. The ability of (R,R,R,R,R,R)-12 to act as a chiral solid-liquid phase-transfer catalyst in an asymmetric Michael addition is compared with the deficiencies of other chiral di- and tetra-substituted 18-crown-6 derivatives, both with respect to product conversions and chirality transfers from catalysts to products

ChemInform Abstract: New Anhydrous Fluorinating Systems: The Combination of Crown‐Ethers and Cesium Fluoride. A Relative Rate Study.

Abstract New, anhydrous fluorinating systems are presented. 18-Crown-6 or dibenzo-24-crown-8 act as solid-liquid phase transfer catalysts with cesium fluoride. A catalytic amount of these crown ethers with CsF increased the rate of fluorodestannylation of trialkyltin mercaptides (used as a good fluoride probe) by a factor of 5–7. In addition, alkyl bromides, such as benzyl bromide, reacted in a similar way. Kinetic evidence for “sandwich” or “edge” complexes with the cesium cation and 18-crown-6 is presented.

Ptc Induced Acylation of Active Methylenes

Abstract Acylation, benzoylation, toluylation and related reactions of active methylenes, e.g. indene, fluorene and diethylmalonic ester is enhanced by the use of solid-liquid phase transfer catalyst. An interesting rearrangement with phthaloyl chloride is reported under identical conditions.