Ethers phenyl, reactions with

Although this work is still incomplete, it shows that some tertiary oxonium ions are formed in the reaction, but that by far the greater part of the active species are secondary oxonium ions. The origin of the tertiary oxonium ions, which yield the involatile phenyl ether by reaction with C6H5CT, is not at all clear at present. Some may be formed from an impurity in the monomer and others may arise from a slow side-reaction. 

Monophenylation of dials. Isolated hydroxyl groups are inert to 1, but diols are converted into monophenyl ethers on reaction with 1 in refluxing CH Cl,. Yields are high in reactions with vtc-diols, but fall to 40-50% when the hydroxyl groups are separated by three or four methylene groups. In the reactions of /-butylcyclohexanediols with 1, the axial epimer reacts much more rapidly than the equatorial one. Preferential phenylation of axial hydroxy groups of pyranosides is also observed. 

Aryl hydroxy groups have been removed by first converting them into an ether by reaction with a heterocycle such as l-phenyl-5-chlorotetrazole (61) and then hydrogenolyzing the ether with platinum or palladium (Eqn. 20.42).97-99 other aryl ether groups that are readily hydrogenolyzed to give the benzene are the benzoxazole, 62, > sulfonates, 63, and phosphates, 64. ... 

Bromobenzene is converted into t-butyl phenyl ether by reaction with potassium t-butoxide in DMSO at 25° for 15 hrs. (86% yield) the reaction is much slower in t-butanol."... 

Cram and co-workers describe a procedure for the conversion of bromo-benzene into phenyl t-butyl ether by reaction with potassium t-butoxide in dimethyl sulfoxide at 125-130° for 1 minute. Benzyne is assumed to be an intermediate. 

Treatment of oestrone with tetraphenylbismuth monotrifluoroacetate gave oestrone phenyl ether and exemplified, in part, a new procedure for aryl ether formation.31 A detailed study was reported of the formation of benzyl ethers by sequential reaction of alcohols with chloro(phenylmethylene)dimethylammonium chloride and sodium hydrogen telluride.32 Steroidal alcohols, inter alia, were converted into hydrolytically stable silyl ethers by reaction with B N Sil or BulPh2I which were generated in situ from the selenosilane and iodine.33 The 5a-hydroxycholestane (21) was protected in this way. 

It was subsequently found that this reaction is not restricted to glycols. Ether-alcohols, amino-alcohols and benzoin were also prone to the phenylation reaction with triphenylbismuth diacetate (47). 5 In the case of the amino-alcohol, the amino group is preferentially phenylated to afford the -phenyl derivative, which can undergo subsequently a second arylation. This second arylation occurs both on the nitrogen and oxygen atoms, preferentially on the oxygen rather than on the aniline-type nitrogen. 

This copper-catalysed phenylation reaction with triphenylbismuth diacetate is not limited to glycols as it has been extended to the arylation of other hydroxylic substrates such as phenols and enols.27 Variously substituted phenolic substrates have been selectively 0-phenylated under very mild neutral conditions (1 to 24 hours at room temperature in methylene dichloiide). The best yields were obtained with metallic copper used as the catalyst. The electronic nature of the substituents of the phenol did not influence the yields (4-nitro, 97% 3,5-dimethoxy, 90%). Only steric hindrance of the 2- and 6-substituents interfered with the reactivity. Thus only 26% of the 0-phenyl ether was obtained in the phenylation of 2,4-di-rerr-butylphenol, and no phenylation took place in the case of 2,4,6-tri-rer/-... 

Terminal I,3-allylic acetates or allylic phenyl ethers by reaction with catalytic quantities of Pd(OAc>2 and P(CeH5)3. ... 

Alternately, the acetal-protected polymers have also been prepared by chemical modification on poly(vinylphenol) by reacting the polymer with vinyl ethers using PFTS as the catalyst. ile satisfactory results were obtained with chemical modification using methyl vinyl ether, the reaction with vinyl phenyl ether showed a low efficiency of blocking the phenolic groups as FT-IR studies indicated that the chemically modified polymer still showed some unprotected... 

Intermolecular reactions with typical cycloaddition components are also possible. Phenyl isocyanate in ether converts triisopropyldiaziridinimine (182) to the 1,2,4-triazolidine under mild conditions. Labeling with a deuterated isopropyl group revealed that cycloaddition is not preceded by N—N cleavage, which should have resulted in deuterium randomization (77AG(E)109). 

Vinyl ethers undergo many cycloaddition reactions similar to those which take place with enamines. In general, however, these cycloaddition reactions with vinyl ethers take place less readily than those with enamines. These reactions include cycloaddition of vinyl ethers with ketene (200-205), phenyl isocyanate (206), sulfene (207,208), methyl acrylate (209), diethyl acetylenedicarboxylate (210), and diphenylnitrilimine (183). 

Repeat this analysis for the reaction of phenyl methyl ether with HI leading to phenol and methyl iodide or methanol and phenyl iodide and involving protonated phenyl methyl ether as an intermediate. (Note In this case, the appropriate empty molecular orbital is LUMO+2 the LUMO is concentrated primarily on the CO bond.) Which reaction, with ethyl propyl ether or phenyl methyl ether, appears to be more likely to give selective ether cleavage ... 

The cyclization of l-alkoxybut-l-en-3-ynes with hydrazine was first achieved by Franke and Kraft (55AG395). By heating 1-methoxybut- l-en-3-yne with hydrazine sulfate in an aqueous alcohol medium they obtained 3(5)-methylpyrazole (13) in high yield. Winter (63HCA1754) used the cyclization of 1-methoxybut-l-en-3-yne with hydrazine hydrate and phenylhydrazine to establish the structure of the initial enyne ether [in this case a mixture of l-phenyl-3(5)-propylpyrazoles was obtained]. The reaction with hydrazine sulfate gives only one product, 3(5)-propyl-pyr azole. 

In a more recent work the same research group has applied cyclic and acyclic vinyl ethers in the oxazaborolidinone-catalyzed 1,3-dipolar cycloaddition reaction with nitrones [30]. The reaction between nitrone 5 and 2,3-dihydrofuran 6 with 20 mol% of the phenyl glycine-derived catalyst 3c, gave the product 7 in 56% yield as the sole diastereomer, however, with a low ee of 38% (Scheme 6.9). 

To a stirred suspension of 10 grams (35 mmol) of 7-chloro-5-phenyl-3H-1,4-benzodiazepin-2(1H) one 4-oxide in approximately 150 ml of methanol was added in portions an excess of a solution of diazomethane in ether. After about one hour, almost complete solution had occurred and the reaction mixture was filtered. The filtrate was concentrated in vacuo to a small volume and diluted with ether and petroleum ether. The reaction product, 7-chloro-1-methyl-5-phenyl-3H-1,4-benzodiazepin-2(1 H)-one 4-oxide, crystallized in colorless prisms. The product was filtered off and recrystallized from acetone, MP 188°-189°C. 

A solution containing 741 g (5.0 mols) of 1-phenyl-2-propylidenylhydrazine, 300 g (5.0 mols) of glacial acetic acid and 900 cc of absolute ethanol was subjected to hydrogenation at 1,875 psi of hydrogen in the presence of 10 gof platinum oxide catalyst and at a temperature of 30°C to 50°C (variation due to exothermic reaction). The catalyst was removed by filtration and the solvent and acetic acid were distilled. The residue was taken up In water and made strongly alkaline by the addition of solid potassium hydroxide. The alkaline mixture was extracted with ether and the ether extracts dried with potassium carbonate. The product was collected by fractional distillation, BP B5°C (0.30 mm) yield 512 g (68%). 

According to U.S. Patent 2,676,964 to 1.0 mol of potassium amide in 3 liters of liquid ammonia, is added 1.0 mol of 2-benzylpyridine. After 15 minutes, 1.1 mols of 3reaction product decomposed with water and ether extracted. The ether layer is dried over Sodium sulfate and after evaporation the residue is distilled, giving the 3-phenyl-3-(2-pyridyl)-N,N-dimethylpropylamine, BP 139°-142°C/1-2 mm. The maleate is produced by reaction with maleic acid. 

Butyl alcohol in synthesis of phenyl 1-butyl ether, 46, 89 1-Butyl azidoacetate, 46, 47 hydrogenation of, 46, 47 1-Butyl chloroacetate, reaction with sodium azide, 46, 47 lre l-4-i-BUTYLCYCLOHEXANOL, 47,16 4-(-Butylcyclohexanonc, reduction with lithium aluminum hydride and aluminum chloride, 47, 17 1-Butyl hypochlorite, reaction with cy-clohexylamine, 46,17 l-Butylthiourea, 46, 72... 

Silver fluoborate, reaction with ethyl bromide in ether, 46, 114 Silver nitrate, complexing with phenyl-acetylene, 46, 40 Silver oxide, 46, 83 Silver thiocyanate, 45, 71 Sodium amide, in alkylation of ethyl phenylacetate w ith (2-bromo-ethyl)benzene, 47, 72 in condensation of 2,4-pentanedione and 1 bromobutane to give 2,4-nonanedione, 47, 92 Sodium 2 ammobenzenesulfinate, from reduction of 2 mtrobenzenesul-finic acid, 47, 5... 

L-Pkenylalanine, reaction with phthalic anhydride to yield N-phthalyl-L-phenylalanine, 40,82 Phenyl terf-BUTYL ether, 41, 91 a-Phenylethylamine, N-chlorination of, 41,82... 

Herbert and Hay reported a bisphenolic monomer, 3,8-bis(4-hydroxyphenyl)-A-phenyl-1,2-naphthalimide (Table 6.1), as well as its corresponding polyf V-phenyl imido aryl ether sulfone) via transimidization reactions with hydrazine monohydrate, aliphatic amines, and an amino acid.193 These polysulfones with... 

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