Methoxymethyl-benzene

Benzenemethanol, a-phenyl-. See Benzhydrol Benzenemethanol, a,a,4-trimethyl-. See Tri methyl benzyl alcohol Benzene, methoxy. See Anisole Benzene, (methoxymethyl)-. See Benzyl methyl ether... 

CAS 538-86-3 EINECS/ELINCS 208-705-7 Synonyms Benzene, (methoxymethyl)- Ether, benzyl methyl (Methoxymethyl) benzene a-Methoxytoluene Methyl benzyl ether a-Methylbenzyl ether Empirical CsHioO Formula C6H5CH2OCH3 Properties Liq. sol. in alcohol, ether sol. 3000 mg/l in water (20 C) m.w. 122.17 sp.gr. 0.949 vapor pressure 1.5 mm Hg m.p. -52.6 C b.p. 174 C flash pt. 53 C ref. index 1.5016 Toxicology TSCA listed... 

This derivative is stable to TsOH/benzene at reflux and to Cr03/H. It is stable to NBS// . In the formation of this derivative formaldehyde from formalin can react with a C,-hydroxyl group to form a methoxymethyl ether. Paraformaldehyde can be used to avoid formation of the ethers. ... 

The carbenoid displacement reaction (see Section 1.4.5.2.1.4.) of the optically active acetoxy sulfide derivative 19 (or the corresponding methoxymethyl ether) with diazomalonate in the presence of a catalytic amount of rhodium acetate in refluxing benzene affords the tram-alkylation productl22. 

In contrast to earlier known imines, those imines derived from a-(methoxymethyl)benzene-ethanamine, which allow formation of a rigid chelate by additional coordination of the lithium with the methoxy group, enabled the preparation of a-alkylated cyclic ketones in very high enantiomeric excesses (90-99% ee)7,8. However, alkylations of imines derived from medium ring ketones were accomplished in 30-82% ee9. The alkylation of acyclic ketones was performed with enantiomeric excesses of more than 75 % and, in the case of the imine derived from 4-heptanone, proceeded with complete asymmetric induction10. 

The transition state of singlet carbene cycloaddition to alkenes involves an electrophilic approach of the vacant p orbital to the n bond of alkenes. By contrast, the first step of the triplet addition process may involve the in-plane a orbital of the carbene. As in the case of C—H insertion (see Section 5.1), the difference in the transition structure between the singlet and triplet cycloaddition becomes important in the intramolecular process, especially when approach to a double bond is restricted by ring strain. Direct photolysis of ( )-2-(2-butenyl)phenyldiazomethane (99) in the presence of methanol gives l-ethenyl-l,la,6,6fl-tetrahydrocycloprop [fljindene [100, 29%, (E/Z)= 10 1] and l-(2-butenyl)-2-(methoxymethyl)benzene (101, 67%). Triplet-sensitized photolysis results in a marked increase in the indene (52%, EjZ) = 1.3.T) at the expense of the ether formation (4%) (Scheme 9.30). On the other hand, direct photolysis of phenyldiazomethane in an equimolar mixture of... 

BASF AG CRBPII dba DBN DBU DIBAL-H DMAP DMF DMF-DMA DMPU HMDS HMPA HMPT H-LR LDA LDE LRAT MCPBA MOM NMO NMP PCC PhH = Badische Anilin- Soda Fabrik AG = cellular retinol-binding protein type II r dibenzylideneacetone = 1,5-diazabicyclo[4.3.0]non-5-ene = l,8-diazabicyclo[5.4.0]undec-7-ene = diisobutylaluminium hydride = 4-dimethylaminopyridine = A V-dimethylformamide = A,V-dimethylformamide, dimethylacetal = 1,3 -dimethyl-3,4,5,6-tetrahydro-2( 1H)-pyrimidone = hexamethyldisilazane = hexamethylphosphoramide = hexamethylphosphorous triamide = Hoffmann-La Roche = lithium diisopropylamide = lithium diethylamide = lecithin retinol acyltransferase = m-chloroperbenzoic acid = methoxymethyl = iV-methylmorpholine oxide = l-methyl-2-pyrrolidinone = pyridinium chlorochromate = benzene... 

The esterification of l-benzyM-(phenylamino) piperidine-4-carboxylic acid with ethanol and H2SO4 gives the corresponding ethyl ester, which is reduced with LiAIH2(0CH2CH20CH3)2 in benzene affording 1-benzyl-4-(phenylamino)piperidine-4-methanol. The methylation of this compound with methyl iodide and NaH in HMPA yields 1 -benzyl-4-methoxymethyl-4-(phenylamino)-... 

Acetal-acetal interchange. Formaldehyde and acetaldehyde acetals can be prepared from methoxymethyl ethers and ethoxyethyl ethers, respectively, by reaction with TsOH in refluxing benzene. 

To a solution of 4.2 g of lithium aluminum hydride in 420 ml of ether under a nitrogen atmosphere and cooled in a ice bath was added dropwise a solution of 99 g of tributyltin chloride in 210 ml of ether. The cooling bath was removed and stirring continued at ambient temperature for 1.5 hours. To the cooled solution was added 260 ml of water. The organic layer was washed with water and dried. This solution was added slowly at 15°C to a solution of (+)-2p,4p-dihydroxy-3a-iodo-5a-(methoxymethyl)cyclopentane-ip-acetic acid y-lactone 4-benzoate in 240 ml of benzene. Then the solution was evaporated and the product was stirred with water. Yield of (-)-3a,5a-dihydroxy-2p-(hydroxymethyl)cyclopentane-la-acetic acid y-lactone 3-benzoate 93%. 

Lithium naphthalenide (prepared from lithium and 1.33 equivalents of naphthalene) also reductively cleaves benzyl ethers [Scheme 4.143],262 Some functionalities survive the reaction conditions like carbon-carbon double bonds, benzene rings, THP ethers, stlyl ethers and methoxymethyl ethers. A ketone group can be present but its prior conversion to an enolate is necessary. A similar transformation, but with a catalytic amount of naphthalene, has been reported.263 Although allyl ethers are also cleaved by the procedure, the selective deprotec-... 

As an alternative to the diradical ring closure that occurs with the 3 -indazole ring contraction, the employment of a 1,3-elimination from an ortho, a-disubstituted aromatic has much appeal for cycloproparene formation, not least because of the simplicity of the process and the ready availability of the starting materials. It is not surprising, therefore, that such a report appeared as early as 1974. Radlick and Crawford found that 1-bromo-2-(methoxymethyl)benzene (33) underwent lithium-halogen exchanged and cyclization to 1 upon treatment with butyllithium. The yield was a modest but acceptable 30%. In similar vein, the cyclization methodology provided rocketene (34) albeit in 5% yield (equation 7a). ... 

Bis[methoxymethyl]-2,S-diphcnylte1lurophene 430 mg (1 mmol) of 3,4-bis[chloromethyl]-2,5-diphenyl-tellurophene are added to a solution of sodium methoxide prepared from 40 ml of absolute methanol and 200 mg (8.7 mmol) of sodium and the mixture is heated under reflux for 10 h. The mixture is then allowed to cool to 20°, poured into water, and extracted several times with diethyl ether. The combined extracts are dried with anhydrous sodium sulfate, filtered, and the filtrate is evaporated. The residue is chromatographed on silica gel with benzene as the mobile phase to give the product as a light yellow oil yield 350 mg (83%). l,3-Diphenyl-4//,6//-selenophene[3,4-c]tellurophene A solution of disodium selenide, prepared from 1.58 g (20 mmol) of selenium and 0.92 g (40 mmol) of sodium in liquid ammonia, in absolute methanol is saturated with nitrogen. 1.28 g (3 mmol) of 3,4-bis[chloromethyl]-2,5-diphenyltellurophene are added and the mixture is refluxed under nitrogen for 15 h. The mixture is then filtered, the filter cake is dissolved in chloroform in the presence of activated charcoal, filtered, and the product is recrystallized from chloroform/methanol yield 0.79 g (60%) m.p. 220°... 

Methoxycarbenium ion is an ambident electrophile reaction can occur at either C or O. Nucleophilic attack at the C atom results in methoxymethylation. Displacement of formaldehyde results in methylation of the nucleophile. The latter reaction is prevalent with aromatics. Thus the reaction of the reagent with benzene gives toluene in high yield. 

A readily hydrolysable ether of a phenol is its methoxymethyl derivatives. The methoxymethyl ethers are hydrolysed in dil. HCl or by traces of pTSA in benzene. Besides ready removability, CH2OCH3 is also readily introduced. The phenols then are preferably converted into their methoxymethyl derivatives before a lithiation reaction is carried out... 

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