Methylphenylcarbinol

Sales demand for acetophenone is largely satisfied through distikative by-product recovery from residues produced in the Hock process for phenol (qv) manufacture. Acetophenone is produced in the Hock process by decomposition of cumene hydroperoxide. A more selective synthesis of acetophenone, by cleavage of cumene hydroperoxide over a cupric catalyst, has been patented (341). Acetophenone can also be produced by oxidizing the methylphenylcarbinol intermediate which is formed in styrene (qv) production processes using ethylbenzene oxidation, such as the ARCO and Halcon process and older technologies (342,343). 

Rhodium (2J) and ruthenium are excellent catalysts for the reduction of aromatic rings. It is with these catalysts that the best chance resides for preservation of other reducible functions (2,10,13,18,41,42,52). Rhodium (41) and ruthenium (45) each reduced methylphenylcarbinol to methylcyclohexyl-carbinol in high yield. Palladium, on the other hand, gives ethylbenzene quantitatively. Water has a powerful promoting effect, which is unique in ruthenium catalysis (36). 

Phenyl-fra-dioxane was obtained by Prins2 by the reaction between styrene and formaldehyde in the presence of sulfuric acid. The correct structure was pointed out by Fourneau, Benoit, and Firmenich.4 The above procedure is essentially that given by Shortridge 6 and by Beets 3 and mentioned in a patent. Methylphenylcarbinol has been substituted for styrene.3... 

Temperature reduction generally provides a severalfold enhancement of nonequivalence magnitude (15,16,19). Cocaine (3) at 20°C shows methylphenylcarbinol-induced nonequivalence in Hj and Hj, and in the A-methyl and 0-methyl resonances of 0.14, 0.03, 0.01, and 0.05 ppm, respectively (15). On lowering the temperature to -40°C, these differences increase to 0.47, 0.06, 0.12, and 0.17 ppm. Only the nonequivalence for Hs changes in sense (zero nonequivalence is observed for H5 at 0°C). Although the increase in nonequivalence magnitude with a reduction of temperature can be attributed in some cases to an increase in the equilibrium constants for CSA-solute association, such enhancement is observed even when the CSA is present in such excess as to cause essentially complete solvation of the enantiomeric solutes (doubtless 3 is such an example). Here, temperature reduction must also increase the intrinsic spectral differ-... 

Styrene is produced by the catalytic vapor phase dehydrogenation of ethylbenzene. Ethylbenzene is made by the Friedel-Crafts condensation of ethylene and benzene. Styrene is also produced by the palladium acetate-catalyzed condensation of ethylene and benzene and by the dehydration of methylphenylcarbinol obtained by the propylation of ethylbenzene. Because of the toxicity of styrene, its concentration in the atmosphere must be severely limited. 

A method employing a similar effect is that of Windaus, Weinhold, and Klanhardt,87 who found that digitonin precipitates the digitonide of one (partially) active form of a-terpineol and oc-tetrahydro-/3-naphthol when added to a solution of the racemic form. The method failed with dt-carvomenthol and eM-methylphenylcarbinol and with the majority of... 

METHYLPHENYLBARBITURIC ACID see ENB500 4-METHYLPHENYL BENZOATE see TGXtOO N-METHYL-4-PHENYL-4-CARBETHOXYPIPERIDINE HYDROCHLORIDE see DAM700 METHYLPHENYLCARBINOL see PDEOOO METHYL PHENYLCARBINYL ACETATE see MNT075... 

Aldehydes react very fast and at low temperature (between -70 and 0 C), whereas ketones require higher temperatures and longer reaction times (Tables 2 and 3). In cross experiments performed using benzaldehyde and acetophenone with MeTi(0 )3 in 1 1 1 molar ratios, only the aldehyde was consumed, leading almost quantitatively to its corresponding methylphenylcarbinol." Such features are fully exploited in the synthesis of macrocyclic lactones like (36 equation 18). ... 

G. Csomontayi, A. Panovici, Dehydration and dehydrogenation of methylphenylcarbinol on various catalysts. Rev. Rowmaine Chim. 17 (1972) 525. 

Analogous results were obtained on oxidation of benzyl alcohol, isopropanol, and cyclohexanol with CBT [68JCS(CC)1305 69JCS(C)1474], Methylphenylcarbinol and diphenylcarbinol under these conditions form acetophenone and benzophenone, respectively. Oxidation of alcohols in organic solvents is regarded as a radical chain process in which chlorine is the chain carrier [69JCS(C)1474] (Scheme 81). 

Synonyms Acetic acid, 1-phenylethyl ester Benzenemethanol, a-methyl-, acetate Benzyl alcohol, o-methyl-, acetate Gardenol a-M ethyl benzenemethanol acetate Methylphenylcarbinol acetate Methylphenylcarbinyl acetate s-Phenethyl acetate 1-Phenylethyl acetate o-Phenylethyl acetate... 

Methylphenylcarbinol acetate Methylphenylcarbinyl acetate. See a-Methylbenzyl acetate Methyl phenylcarbinyl butyrate. See a-Methylbenzyl butyrate Methyl phenylcarbinyl formate. See a-Methylbenzyl formate Methyl phenylcarbinyl isobutyrate. See Methylbenzyl isobutyrate... 

Cobalt complexes with pyridine ligands, for example, catalyzed the oxidation of neat ethylbenzene to acetophenone in 70% conversion and 90% selectivity [35]. Mn porphyrin complex catalyzes the ethylbenzene oxidation with dioxygen to 3 14 mixture of methylphenylcarbinole and acetophenone in the presence of acetaldehyde [36]. The system CUCI2-crown ether in the presence of acetaldehyde is efficient as catalyst of oxidation of ethylbenzene, indane, and tetralin by dioxygen (70°C) into the corresponding alcohols and ketones with high TON [37]. The oxidations were established to occur via a radical pathway and not by a metal-oxo... 

The oxidation of ethylbenzene using iron-haloporphyrins in a solvent-free system under molecular oxygen at 70-110°C gives mixture of a-phenylethylhydroperoxide, methylphenylcarbinole, and acetophenone (1 1 1). The catalyst is (TPFPP=5,10,15,20-tetrakis (pentafluorophenyl) porphyrin). Ethylbenzene conversion does not more than 5%. The oxidation occurs via radical pathway [3 9]. The products of ethylbenzene oxidation with air under mild condition (T > 60°C, atmospheric pressure), catalyzed by [TPPFeJ O or [TPPMnJ O ( 0,-oxo dimeric metalloporphyrins, a,-oxo-bis(tetraphenylporphyrinato)iron (manganese)) without any additive are acetophenone and methylphenylcarbinole. The ethylbenzene oxidation is radical chain oxidation in this case also. The ketone/alcohol (mol/ mol) rations are 3.76 ([TPPMnJ O, ethylbenzene conversion - 8.08%), 2.74 ([TPPFe]20, ethylbenzene conversion - 3.73%) [40]. 

Benzaldehyde (BAL), benzyl alcohol (BZA), acetophenone (AP), methylphenylcarbinol (MPC), dimethyl phenylcarbinol (DMPC), and phenol (PhOH), as well as the RH content in cumene and ethylbenzene oxidation processes were examined by GLC [9-14,17], The overall rate of the process was determined from the rate of aceumulation of all oxidation products (toluene, ethylbenzene), or consumption of starting hydrocarbon (cumene). A correlation between RH consumption and product (P) accumulation was established A[RH] = S [P]. 

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