Sodium phenoxide reactions

Thus phenol when subjected to the Schotten Baumann reaction first dissolves in the sodium hydroxide to give sodium phenoxide, which then undergoes CgH COCl + NaOCgH, CgHaCOOCeHj XaCl... 

Salicylic acid. The preparation of salicylic acid by passing carbon dioxide into dry sodium phenoxide at 170-190° is the classical example of the Kolbe-Schmltt reaction. The latter is a method for introducing a carboxyl group directly into a phenol nucleus. 

The furo- and pyranobenzopyranones 114 and 115 are prepared by the reaction of 0-enolate of i(-keto lactone 113[132], The isoxazolc 117 is obtained by the oxidation of the oxime 116 of a, /3- or, d, 7-unsaturated ketones with PdCh and Na2C03 in dichloromethane[l 33], but the pyridine 118 is formed with PdCl2(Ph3P)2 and sodium phenoxide[134]. 

After cleavage the reaction mass is a mixture of phenol, acetone, and a variety of other products such as cumylphenols, acetophenone, dimethyl-phenylcarbinol, a-methylstyrene, and hydroxyacetone. It may be neutralised with a sodium phenoxide solution (20) or other suitable base or ion-exchange resins. Process water may be added to facilitate removal of any inorganic salts. The product may then go through a separation and a wash stage, or go direcdy to a distillation tower. 

Dialkylaminoethyl acryhc esters are readily prepared by transesterification of the corresponding dialkylaminoethanol (102,103). Catalysts include strong acids and tetraalkyl titanates for higher alkyl esters and titanates, sodium phenoxides, magnesium alkoxides, and dialkyitin oxides, as well as titanium and zirconium chelates, for the preparation of functional esters. Because of loss of catalyst activity during the reaction, incremental or continuous additions may be required to maintain an adequate reaction rate. 

Long-chain esters of pentaerythritol have been prepared by a variety of methods. The tetranonanoate is made by treatment of methyl nonanoate [7289-51-2] and pentaerythritol at elevated temperatures using sodium phenoxide alone, or titanium tetrapropoxide in xylene (12). PhenoHc esters having good antioxidant activity have been synthesized by reaction of phenols or long-chain aUphatic acids and pentaerythritol or trimethyl olpropane (13). 

If the ion-exchange resin is used for removing phenol, it is regenerated by employing caustic soda to convert phenol into sodium phenoxide (a salable compound) according to the following reaction ... 

Condensation of sodium phenoxide witli 2,2,2-trifluoroethyl iodide gives a product of direct substitution in a low yield, several other ethers are formed by eliminatton-addition reactions [7] Use of mesylate as a leaving group and hex amethyl phosphoramide (HMPA) as a solvent increases the yield of the substitution [S] Even chlorine can be replaced when the condensation is performed with potassium fluoride and acetic acid at a high temperature [9] (equations 6-8)... 

The nucleophilic reaction of bromotrifluoroethene with alkoxides yields not only the expected addition and addition-elimination products but also a product from a bromophilic reaction of the carbanion intermediate [6] (equation 3) Similar are the reactions of sodium phenoxide with perfluorovinyl ethers in the presence of hexachloroethane or selected vicinal dibromoperfluoroalkanes The intermediate carbanion is trapped in high yield by these sources of Cl or Br, which suggests a... 

Mono-substitution occurs most readily in the stepwise replacement of the halogen substituents of 2,4,6-trichloro-s-triazine with aqueous methanol and sodium bicarbonate (30°, 30 min), the monomethoxy derivative (324) is obtained on heating (65°, 30 min), the disubstitu-ted derivative is formed and on brief heating (65°) with the more basic sodium carbonate or methanolic sodium hydroxide (25°, 3 hr) complete methoxylation (320) occurs. Ethanolic ethoxide (25°, 1 hr) or sodium carbonate (35°) is sufficient to give complete ethoxy-dechlorination. The corresponding phenoxy derivatives are obtained on treatment with one (0°), two (15°, 1 hr), or three equivalents (25-70°, 3 hr) of various sodium phenoxides in aqueous acetone. The stepwise reaction with phenols, alcohols, or thiols proceeds in better yield in organic solvents (acetone or chloroform) with collidine or 2,6-lutidine as acid acceptors than in aqueous sodium bicarbonate. ... 

In order to rationalize the orr/zo-selectivity observed in the reaction of sodium phenoxide 1 with carbon dioxide, the formation of a complex 3 is assumed. By that complexation the carbon dioxide becomes polarized, and its electrophilic character is increased. Complex 3 is of suitable geometry for reaction with the activated ort/zo-carbon center " ... 

Ethers can be prepared by reaction of an alkoxide or phenoxide ion with a primary alkyl halide. Anisole, for instance, results from reaction of sodium phenoxide with iodomethane. What kind of reaction is occurring Show the mechanism. 

Sodium phenoxides can be carboxylated, mostly in the ortho position, by carbon dioxide (the Kolbe-Schmitt reaction). The mechanism is not clearly understood, but... 

Linear phosphazene polymers, obtained from the reaction of ammonium chloride with phosphorus pentachloride in chlorobenzene, may be rendered hydrolytically stable by reaction of one of the terminal chlorine atoms with, for example, sodium phenoxide ... 

Tjandra et al. (1998) have proposed an interfacial reaction model for the kinetics of the reaction between 1-bromo octane and sodium phenoxide to give 1-phenoxyoctane in a nonionic microemulsion. In this model the microemulsion is assumed to consist of the aqueous phase and the interface is covered by a monolayer of surfactant molecules. It is thus possible to assess the interfacial area from the concentration of the surfactant in the microemulsion medium. 

Sodium phenoxide, 32, 75 33, 43, 45 Sodium sulfhydrate, 31, 7 Sodium sulfide nonahydrate, 31, 6 Sommelet reaction, 33, 93 Sorbic acid, S-hydroxy-0-methyl, 3-lactone, 32, 57 Stannic chloride, 33, 91 Stearone, 33, 84 ms-Stilbene, 33, 88 Irans-Stilbene, 33, 89... 

The somewhat analogous Kolbe-Schmidt reaction involves C02 as the electrophile in attack on powdered sodium phenoxide (64b) ... 

The product is almost exclusively sodium o-hydroxybenzoate (salicylate, 71) only traces of the p-isomer being obtained if, however, the reaction is carried out on potassium phenoxide the salt of the p-acid becomes the major product. It has been suggested that the preferential o-attack with sodium phenoxide may result from stabilisation of the T.S. (72) through chelation by NaP in the ion pair ... 

Commereuc and Chauvin studied the effect of ligands on the reaction of ethanol (43). When bis(diphenylphosphino)-1,2-ethane (39) was used with PdCl2 and sodium phenoxide, 1 1 products [l-methoxy-2-butene (40) and 3-methoxy-l-butene (41)] and a 1 2 product [8-methoxy-l,6-octadiene (36)] were obtained in equal amounts. Nickel-PEt3 catalyst gave a mixture of the 1 2 and 1 1 telomers ... 

The reaction was carried out with /3-keto esters, /3-diketones, malonate, a-formyl ketones, a-cyano and a-nitro esters, cyanoacetamide, and phen-ylsulfonylacetate. (PPh3)2PdCl2 was used with sodium phenoxide. Also, Pd(OAc)2 and PPh3 are good catalysts. When bidentate ligand was used, the 1 1 rather than 1 2 addition reaction took place (56). For example, bis(diphenylphosphino) 1,2-ethane (39) produced a mixture of the following 1,4- (59) and 1,2- (60) addition products ... 

One mole of isoprene reacted with one mole of acetoacetate by using a bidentate phosphine as ligand (56). Reaction of 2,3-dimethylbutadiene with acetoacetate was carried out by using PdCl2 in the presence of sodium phenoxide. When PPh3 was used, a 1 2 adduct was obtained. On the other hand, use of P-phenyl-l-phospha-3-methyl-3-cyclopentene (105) at 100°C caused the 1 1 addition to give 3-carbomethoxy-5,6-dimethyl-5-hepten-2-one (106), from which 5,6-dimethyl-5-hepten-2-one (107) was formed. This compound is the useful intermediate for a-irone synthesis (96). 

Although unusual, a nucleophile has occasionally been observed to add to the central carbon of a metal 7r-allyl species to generate a metallacyclobutane intermediate, which can then undergo further transformations. In the reaction between 2,3-dibromopropene and sodium phenoxide under Pd catalysis (Equation (56)), the central carbon of the initially formed 7r-allyl intermediate is attacked by phenoxide to furnish a palladacyclobutane. Displacement of the... 

Since, in Kolbe s synthesis, as here described, the mono-sodium salicylate reacts to some extent with unchanged sodium phenoxide, producing the di-sodium salt, part of the phenol is liberated and excluded from the reaction. The reaction proceeds to completion if the sodium phenoxide is heated to about 150° for a long time, with carbon dioxide under pressure in the autoclave. This is the technical method of Schmitt. 

Hirao et al. (1978a,b) have reported similar results. The rate of reaction of sodium phenoxide with 1-bromobutane was 88 times faster in dimethoxy-ethane than in dioxan. The presence of 0.135 M dibenzo-18-crown-6 [11] in dioxan completely levelled out the difference with dimethoxyethane. It is... 

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