Methylbenzyl ketone

Fig. 4. The cage effect for benzyl- 1-methylbenzyl ketone a function of concentration of the surfactant HDTC1 shows a typical CMC profile...

Asymmetric hydrosilylation of acetophenone, methylbenzyl ketone, and isobutyro-phenone can be achieved using soluble chiral rhodium(i)-diop complexes (49) and polymer-supported catalyst. The optical yield is dependent on the silane used, dihydrosilanes giving higher yields than monohydrosilanes. Similar results are obtained with a-keto-esters. ... 

Figure C2.3.9. Product distribution of dissymmetrical ketone photolysis as influenced by cefyltrimethylammonium chloride (CTAC) micelles. The initial ketone, A(CO)B is photolysed to lose the carbonyl group and to produce tliree products, AA, AB and BB. These data are for benzyl (A) 4-methylbenzyl (B) ketone. Product AA is 1,2-diphenylethane, product BB is 1,2-ditolylethane and product AB is l-phenyl-2-tolyl-ethane. At low CTAC concentration, in the absence of micelles, a random distribution of products is obtained. In the presence of micelles, however, the AB product is heavily favoured. Adapted with pennission from 1571.

Halocarbons, ketone-alcohol reduction, 84 Halogenation, 4-methylbenzyl chloride [reductive halogenation of aldehyde to benzyl chloride], 124 Hemiacetals, reduction of, 97-99 Hemiaminals, reduction of, 99-100 Hemiketals, reduction of, 97-99 Heptene derivatives, alkene to alkane reductions, disubstituted alkenes, 36-38... 

This asymmetric phase-transfer method has been applied to enantio-selective Robinson annelation as shown in Scheme 14 (41). First, alkylation of a 1-indanone derivative with the Wichtetie reagent as a methyl vinyl ketone equivalent in the presence of p-CF3BCNB gives the S-alkylation product in 92% ee and 99% yield. With 1 -(p-trifluoro-methylbenzyl)cinchonidinium bromide, a pseudo-enantiomeric diaste-reomer of p-CF3BCNB, as catalyst, the -alkylation product is obtained in 78% ee and 99% yield. These products are readily convertible to the... 

A soln. of isoduryl phenyl diketone, glacial acetic acid, and a large excess of com. 47%-HJ refluxed 2 hrs. with stirring — 2,4,5,6-tetra-methylbenzyl phenyl ketone. Y 92%. (F. e., in which also a hindered keto group is reduced, s. R. C. Fuson and P. E. Iloch, Am. Soc. 71,1585 (1949).)... 

The reaction of either (R)- or (5)-a-methylbenzylamine (364) with sulphuryl chloride gives the (R,R) and (5,5) N,N bis(a-methylbenzyl) sulphamide 365. When 365 is added to LiAlH4 in the presence of A-benzylmethylamine in tetrahydrofuran, it leads to the asymmetric reduction of prochiral ketones 366 (equation 115)363. Optimization of the reaction was carried out with respect to enantioselectivity and reactivity of the reagents. The use of iV-benzylmethylamine as an additive was found to be superior to ethanol. Reaction at — 20 °C gave 87% selectivity with a one-hour reaction time. Both arylalkyl ketones and dialkyl ketones are asymmetrically reduced in the reaction. 

Michael additions. Despite tremendous efforts spent in achieving catalytic asymmetric Michael additions, effective additives of wide applicability are still quite rare. Interestingly, a polyamine ligand 29 promotes the addition of ketone enolates. With JV-methoxy-N-methyl amides of a,p-unsaturated acids as acceptors, the addition of lithium fS)-(a-methylbenzyl)benzylamide proceeds in a highly diastereo- and enantioselective manner, ascribable to a six-centered transition state in which the conjugated amide adopts an s-cis conformation, ... 

Oxidations were carried out at 85 in chlorobenzene as solvent and substrate catalyst molar ratios of ca. 100 1. Cyclohexanol, and a-methylbenzyl alcohol were converted to the corresponding ketones in high selectivities using TBHP under a N2 atmosphere. The selectivity on TBHP was also > 90%. Good results were also obtained for the selective oxidations of Cyclohexanol, a-methylbenzyl alcohol, tetralol and indanol using 2 as the oxidant and 10 mol% TBHP as initiator. The catalyst could be recycled several times without any loss of activity. A mechanism is proposed for the CrAPO-5 catalyzed oxidation of alcohols. 

Methyl n-amyl ketone Methyl anthranilate Methyl benzoate a-Methylbenzyl acetate a-Methylbenzyl alcohol Methyl cinnamate 3-Methyl-2-cyclopenten-2-ol-1-one 6-Methyl-3,5-heptadien-2-one Methyl a-ionone Methyl isoeuqenol Methyl laurate 1-Methyl-1-methoxycyclododecane Methyl 2-nonenoate Methyl nonyl acetaldehyde Methyl 2-octynoate Methyl pelarqonate Methyl phenylacetate Methyl salicylate Methyl tiqiate Methylundecanal dimethyl acetal Myrcene Nerol... 

Amino-6-ethoxybenzothiazole C9HioN402S2 Sulfamethizole C9H10O 2-Ally I phenol Cinnamyl alcohol 2,4-Di methyl benzal dehyde p-Ethylbenzaldehyde Ethyl phenyl ketone Hydrocinnamaldehyde 4 -Methyl acetophenone 2-Phenyl propanal Propiophenone p-Tolylacetaldehyde C9H10O2 Acetanisole Benzyl acetate m-Cresyl acetate o-Cresyl acetate p-Cresyl acetate p-Ethoxybenzaldehyde Ethyl benzoate Hydrocinnamic acid 2-M ethoxy-4-vi nyl phenol a-Methylbenzyl formate Methyl phenylacetate Methyl p-toluate Phenethyl formate Phenyl glycidyl ether... 

The use of a reductive protocol has allowed the synthesis of chiral amines by the reductive amination of aliphatic ketones mediated by the combination of titanium tetraisopropoxyde, Raney nickel, and hydrogen in the presence of (R) or (5)-a-methylbenzyl amine. The corresponding chiral primary amines were obtained by subsequent hydrogenolysis in 71-78% overall yield and maintained enantiomeric excesses (72-98% ee) [34]. 

Methyl allyl chloride) see Dimethylvinyl chloride Methylamine (Monomethylamine) (2-(Methylamino)ethanol) see A-Methylethanolamine 3-Methylaminopropylamine (Methyl tert-amyl ether) see tert-Amyl methyl ether (Methyl amyl ketone) see Methyl pentyl ketone (2-Methylaniline) see o-Toluidine (3-Methylaniline) see m-Toluidine (Methylbenzene) see Toluene (a-Methylbenzyl alcohol) see 1-Phenylethanol Methyl bromide (Bromomethane)... 

Cineole, 13, is a natural herbicide [73]. Its hydroxy derivative 14 (2-hydroxy-1,4-cineole 1,4-epoxy-p-menthane-2-ol) is a constituent of oil from rhizomes of Ferula jaeschkeana [74]. Its 2-methylbenzyl ether 15 (cinmethylin) is a preemergence grass herbicide [75, 76]. Alcohol 14 can be prepared by microbial hydroxy-lation of 13 [77]. This also produces ketone 16 and its enantiomer [78]. The fragrance of ketone 16 and isomeric l-isopropyl-4-methyl- 7-oxabicyclo[2.2.1] heptan-2-one is very similar to that of 14 and menthone [79]. Mullilam diol 17, a dihydroxy derivative of 13, has been isolated from Zanthoxylum rhetsa, a plant that exhibits antibiotic activity which is prescribed in dyspepsia and diarrhea. The eight-carbon system rengyoxide has been found in Forsythia suspensa fruits [80] (Fig. 4). 

Diaryl triketones do not show the same reactivity as their dialkyl counterparts. This is illustrated by the fact that 19-hr irradiation through Pyrex using the full spectrum of a 1000-W, high-pressure, mercury-vapor lamp was required for 90% disappearance of 250 mg of diphenyl triketone (13) in degassed p-xylene solution. The major products isolated were p,p -dimethylbibenzyl, benzaldehyde, and p-methyl-benzyl phenyl ketone in addition, minor amounts of oxidation products such as p-methylbenzyl benzoate were identified, as well as traces of benzil. Quantum yields for the disappearance of 13 at 436 nm in degassed or air-saturated p-xylene solutions were about 3 x 10 k nearly identical values were obtained... 

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