SYNTHESIS OF N－ARYL－4－METHYLPHENOXYACETAMIDES BY MEANS OF LIQUID－LIQUID PHASE TRANSFER CATALYSIS

ＳＹＮＴＨＥＳＩＳ ＯＦ Ｎ－ＡＲＹＬ－４－ＭＥＴＨＹＬＰＨＥＮＯＸＹＡＣＥＴＡＭＩＤＥＳ ＢＹ ＭＥＡＮＳ ＯＦ ＬＩＱＵＩＤ－ＬＩＱＵＩＤ ＰＨＡＳＥ ＴＲＡＮＳＦＥＲ ＣＡＴＡＬＹＳＩＳ￥ＴａｉＢａｏＷＥＩ；ＪｉＣｈｏｕＣＨＥＮ；ＹｏｕＭｉｎｇ...     

SYNTHESIS OF 1-O-ACYL-2,3,4-TRI-O-ACETYL-β-D-XYLO-AND ARABINOPYRANOSES BY PHASE TRANSFER CATALYSIS

The acetylated xylo-and arabinopyranosyl esters(1-8) were obtained in high yields with stereoselectivity by phase-transfer catalyzed (PTC) synthesis, and their structures were confirmed by elemental analysis and IR, ~1H-NMR spectral data.     

STUDIES ON DOPAMINE RECEPTORS AND TETRAHYDROPROTOBERBERINES．Ⅱ．QUANTUM CHEMISTRY OF LIGAND－RECEPTOR INTERACTION

ＳＴＵＤＩＥＳＯＮＤＯＰＡＭＩＮＥＲＥＣＥＰＴＯＲＳＡＮＤＴＥＴＲＡＨＹＤＲＯＰＲＯＴＯＢＥＲＢＥＲＩＮＥＳ．Ⅱ．ＱＵＡＮＴＵＭＣＨＥＭＩＳＴＲＹＯＦＬＩＧＡＮＤ－ＲＥＣＥＰＴＯＲＩＮＴＥＲＡＣＴＩＯＮ￥ＹｕｎＴＡＮＧ；ＫａｉＸｉａｎＣＨＥＮ；Ｈｕａ...     

Synthesis of α-Aminophospiionic Esters by Solid-Liquid Phase Transfer Catalysis

Abstract

(1-aminoalkyl)phosphonic acids are important amino acids with interesting biological properties (1). They are available by various procedures (2). However, a potentially efficient and direct route not very well documented is the use of schiff bases derived from diethyl-aminomethylphosphonate. These substrates have been used to prepare a-alkylated phosphonic aminoacids using strong bases under anhydrous conditions (3). We report here a simple method using solid-liquid phase transfer catalysis (PTC) as wel1 as solid-liquid PTC without solvent:     

The Synthesis of Symmetrical Azobenzenes from Anilines by Phase Transfer Catalysis

Azobenzeneshavebeenwidelyutilizedasdyesandanalyticalreagents'.Theycanals0beusedasmaterialofnon-linearoptics,0pticinformationstoringmateriaIinlaserdiskanddyeswithoilsolubilityinphotochromyinmoderntechnol0gy"'.TheoxidationofsubstitutedsemicarbazidestoazocompoundswithseveralreagentssuchasNBS(N-bromosuccinimide)/pyridine',KClO,M,S0'NeS0",DMF-NO.'and2,4,6-(t-C'H,),C,H,OWh,Fe(CN),/Nhasbeenreportedbyus.The0xidationofsubstitutedanilinestoazobenzeneswithavarietyofreagentssuchasphenyli0d0acet…     

BICENTRAL POLYMER SUPPORTED PHASE TRANSFER CATALYST POLYSTYRENE－SUPPORTED POLYETHYLENE GLYCOL AND PYRIDINIUM SALT

ＢＩＣＥＮＴＲＡＬＰＯＬＹＭＥＲＳＵＰＰＯＲＴＥＤＰＨＡＳＥＴＲＡＮＳＦＥＲＣＡＴＡＬＹＳＴＰＯＬＹＳＴＹＲＥＮＥ－ＳＵＰＰＯＲＴＥＤＰＯＬＹＥＴＨＹＬＥＮＥＧＬＹＣＯＬＡＮＤＰＹＲＩＤＩＮＩＵＭＳＡＬＴＹａｎｇＪｉａｎｗｅｎ（Ｉｎｓｔｉｔｕｔｅｏｆ...     

A NOVEL PREPARATION OF o－ETHOXYPHENOL FROM o－CHLOROPHENOL IN THE PRESENCE OF PHASE TRANSFER CATALYSIS UNDER MICROWAVE IRRADIATION

ＡＮＯＶＥＬＰＲＥＰＡＲＡＴＩＯＮＯＦｏ－ＥＴＨＯＸＹＰＨＥＮＯＬＦＲＯＭｏ－ＣＨＬＯＲＯＰＨＥＮＯＬＩＮＴＨＥＰＲＥＳＥＮＣＥＯＦＰＨＡＳＥＴＲＡＮＳＦＥＲＣＡＴＡＬＹＳＩＳＵＮＤＥＲＭＩＣＲＯＷＡＶＥＩＲＲＡＤＩＡＴＩＯＮＹｕＬｉｎＪＩＡＮＧ；Ｊ...     

A Review of “Phase Transfer Catalysis—Selected Problems and Applications”

Abstract

Yuri Goldberg (Institute of Organic Synthesis, Latvian Academy of Sciences, Riga, Latvia), Gordon and Breach Science Publishers, 1992, 456 pp. $170.     

Selective Formation of Methyl α-Methylsulfanyl Dimethylphosphonothioacetate and Thiopropanoate by Phase Transfer Catalysis

The sulfanylation of methyl dimethylphosphonothioacetate was investigated by a phase transfer catalysis procedure which was shown to be superior to the noncatalytic method. The possibility of electrophilic substitution of the α-sulfanylated phosphonothioacetate to give a quaternary α-carbon atom is shown by the reaction with methyl iodide.

     

POLYMERIZATION BY PHASE TRANSFER CATALYSIS. 25. SYNTHESIS OF POLYCARBONATES AND POLYTHIOCARBONATES DERIVED FROM DIPHENOLS CONTAINING GERMANIUM AND SILICON IN THE MAIN CHAIN†

Polycarbonates and polythiocarbonates derived from diphenols containing Si or Ge, bis(4-hydroxyphenyl)-dimethyl-germane (I), bis(4-hydroxyphenyl)-diphenyl-germane (II), bis(4-hydroxy-phenyl)-dimethyl-silane (III), and bis(4-hydroxyphenyl)-diphenyl-silane (IV), and phosgene (a) or thiophosgene (b), respectively, were synthesized under phase transfer conditions using several phase transfer catalysts. The results were evaluated by the yields and η_inh values, showing that this technique was effective for the synthesis of this kind of polymers. The yields were low compared with those obtained with other diphenols, due probably to the use in this work of stoichiometric amounts of NaOH to avoid the decomposition of the diphenol, which hindered a salting out effect of the diphenolate to the organic phase.

     

Potassium Ferricyanide Mediated Cyclisation of 2′-Hydroxychalcones to Flavanones Using Phase Transfer Catalysis

Flavanones have been synthesised by cyclisation of 2′-hydroxychalones with potassium ferricyanide using phase transfer catalysis.     

Reduction of 2′-Hydroxy Chalcones Under Phase Transfer Catalysis—A new Method for the Synthesis of Flavan-4-OLS

Reduction of 2′-hydroxy chalcones under phase transfer catalysis conditions is discussed. The products are identified as 2,4-cis-fLavan-4-OLS.     

PHOTOINDUCED INTRAMOLECULAR CHARGE TRANSFER IN SELF－ASSEMBLY．1．AGGREGATION AND DUAL FLUORESCENCE OF ETHYL P－DIDECYLAMINOBENZOATE IN DIOXANE－WATER BINARY SOLVENT

ＰＨＯＴＯＩＮＤＵＣＥＤＩＮＴＲＡＭＯＬＥＣＵＬＡＲＣＨＡＲＧＥＴＲＡＮＳＦＥＲＩＮＳＥＬＦ－ＡＳＳＥＭＢＬＹ．１．ＡＧＧＲＥＧＡＴＩＯＮＡＮＤＤＵＡＬＦＬＵＯＲＥＳＣＥＮＣＥＯＦＥＴＨＹＬＰ－ＤＩＤＥＣＹＬＡＭＩＮＯＢＥＮＺＯＡＴＥＩＮＤＩＯＸＡＮ...     

Efficient and Convenient Synthesis of Diethers from Furoin Under Ultrasound and Solid-liquid Phase Transfer Catalysis Conditions

Introduction Compounds having an active hydroxy group,such as,acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst(PTC).The reaction is usually carried out in the presence of concentrated aqueous sodium or potassium hydroxide and a phase transfer catalyst,such as,quaternary ammonium     

Efficient and Convenient Synthesis Ultrasound and Solid-liquid Phase of Diethers from Furoin Under Transfer Catalysis Conditions

Compounds having an active hydroxy group, such as, acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst （PTC）. The reaction is usually carried out in the presence of con-centrated aqueous sodium or potassium hydroxide and a phase transfer catalyst, such as, quaternary ammonium salts^[1-3] species, miscible which facilitate the interphase transfer of making reactions between reagents in two im-phases possible. The reaction involves a series of equilibrium and mass-transfer steps.     

Phase Transfer Catalysis: Improved Synthesis of Ketones from β-Keto Esters in an Aoueous Medium

β-Keto esters can be easily decarbethoxylated to yield ketones in dilute aqueous potassium hydroxide that contains 0.1% hexadecyltrimethylammonium bromide in 45 minutes at 80°C; yields exceed 75% and work-up requires only a single step.     

Synthesis of Phosphorus-Containing Podands―Analogs of Diglycolamide Based on Diphenyl- and Dibutylphosphorylmethanol under Phase Transfer Catalysis Conditions

A convenient method for preparation of phosphorus-containing podands R₂P(O)CH₂OCH₂X, where X = C(O)NBu₂; P(O)R′₂, R = R′ = Ph, Bu, R = Ph, R′ = Bu via OH-alkylation of phosphorylmethanols under the phase transfer conditions in the presence of Cs₂CO₃ was developed. Carbamoyl-substituted dimethyl ethers were synthesized via transformation of phosphorylmethanols to phosphorylmethoxyacetic acids, followed by amidation. Symmetrical bisphosphoryl substituted dimethyl ethers were obtained by reaction of phosphorylmethanols with tosyl chloride in the presence of Cs₂CO₃. The synthesis of unsymmetrical substituted ether in the presence of Cs₂CO₃ was complicated by transesterification of phosphorylmethyl tosylate resulting in the formation of symmetrical dimethyl ethers as byproducts.     

Studies on Solid-Liquid Phase Transfer Equilibrium of Onium Salts(Ⅱ)

The present paper contains the effects of the ammonium ion, counter ion, solvent and anion being transferred on the solid-liquid phase transfer equilibrium constant of quaternary ammonium salts. The most striking difference between solid-liquid and liquid-liquid phase transfer equilibriums is that the length of alkyl chain shows a large effect on the latter but little on the former This means that the chain length affects only the hydrophobicity, rather than the lipophilicity.Keywords Quaternary ammonium salt, Phase transfer catalysis, Equilibrium constant, Hydrophobicity, Lipophilicity     

One-pot Synthesis of 1-Aryloxyacety l-4-(4''''-nitrophenyloxyacetyl)-thiosemicarbazides under Phase Transfer Catalysis and Microwave Irradiation

1,4-Disubstituted thiosemicarbazides have attracted much attention in recent years because of their fungicidal1-2, bactericidal3-4 and tuberculostatic5-6 activities. Meanwhile, aryloxy acetic acid derivatives have also been used as herbicides and plant-growth regulators7-10. These applications prompt us to develop a simple and rapid synthetic method to prepare a series of new compounds bearing both thiosemicarbazide and aryloxyacetyl moieties, with the object of obtaining new biologically ac…