2-Phenylethyl acetate

Williams employed complexes of Al, Rh, or Ir in combination with Pseudomonas Jluorescens lipase (PFL) for the DKR of 1-phenylethanol. The best results were obtained using Rh2(OAc)4 as the catalyst for the racemization, and 60% conversion of the alcohol to give 1-phenylethyl acetate in 98% ee was obtained (Figure 4.6) [19]. At higher conversion, the enantiomeric excess dropped and 76% conversion gave 80% ee. 

Diacetoxylation of olefins with benzenetellurinic anhydride (typical procedure) To a solution of (PhTe0)20 (0.95 g, 2.1 mmol) in dry HOAc (15 mL) is added styrene (0.208 g, 2.0 mmol) in HOAc (4 mL) and 98% H2SO4 (0.020 g, 0.2 mmol) in HOAc (1 mL). The mixture is gently refluxed for 24 h, which turns red with deposition of a small amount of elemental tellurium. After removal of tellurium (0.071 g, 0.56 mmol) by fdtration, the solvent is evaporated, the residue extracted with ether and the ether extract dried (MgS04). Chromatography on Si02 gives the v/c-diacetate (0.363 g (82%)) and 1-phenylethyl acetate (0.029 g (9%)). 

Dibut-3-enyl carbonate /-Propyl acetate, neat Ethyl acetate 1-phenylethyl acetate ... 

Determination of Molar Coefficients of Absorbance of Labeled and Unlabeled 1-Phenylethyl Acetates [22]... 

A specific example concerns the kinetic resolution of 1-phenylethyl acetate, previously used to illustrate the NMR-based ee assay (see Section 9.3.2). The optimal way to proceed is to apply 13C labeling in the carbonyl moiety, i. e., to prepare a pseudo racemate comprising a 1 1 mixture of (.S)-13C-4 and (R)-4 (Section 9.3). Figure 9.7 shows part of the FTIR spectrum of a 1 1 mixture of (R)-4 and (.S)-13C-4, illustrating the anticipated shift of the respective carbonyl-stretching vibration, which allows quantification of the pseudo enantiomers [22]. 

After preparation of a stock solution (0.200 M) of (R)- 1-phenylethyl acetate ((i )-4) and (S)-( 1 -phenylethyl)-1 -13C-acetate ((b1)-l3C-4) in cyclohexane, the solutions are diluted with cyclohexane to concentrations of 0.180, 0.160, 0.140, 0.120, 0.100, 0.080, 0.060, 0.040, and 0.020M (total volume lmL). The absorbance of the resulting samples is measured with a FTIR spectrometer at the corresponding absorption maxima of the carbonyl-stretching vibration ((i )-4 1751 cm-1 (S)-13C-4 1699 cm-1) with a thickness of the layers of 25.0 pm, performing 32 scans at a resolution of 4 cm-1. The molar coefficients of absorbance are determined by linear regression, with correlation coefficients >0.995. Analysis of synthetic mixtures of the pseudo enantiomers of 1-phenylethyl acetate is performed under the same conditions at a concentration of 0.10 M. 

Scheme 6.13 Benzylation of different arenes with 1-phenylethyl acetate CCyield (regioselectivity). Reaction conditions 0.5 mmol 1-phenylethyl acetate, 10mol% FeCI3, 2.0mmol arene, 5mL CH2CI2, 50°C, 20 h (a) 5 mL arene, no solvent (b) 5 mL MeN02, 120°C (c) 5 mL MeNQ2.

Synonyms p-Cumylphenyl acetate Phenol, p-(a,a-dimethylbenzyl)-, acetate Phenol, 4-(1-methyl-1-phenylethyl)-, acetate... 

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... 

The known free-radical decomposition of aryl nitrosoamides (ArN(NO)COR ) and the report that nitrosoamides of 0-alkyl-hydroxylamines decompose by a free-radical pathway indicate that free-radical processes might occur in the normal nitrosoamide decomposition. In fact, the aliphatic nitrosoamides have been used as initiators at elevated temperatures for the polymerization of styrene and other olefins At, or near, room temperature, however, it appears that free radicals are not formed in the nitrosoamide decomposition. It has been found, for example, that (1) COj (a product of the decarboxylation of carboxyl radicals) is not formed in the decomposition (2) the scavenger nitric oxide has no effect on the reaction (3) normal products and no polymer are formed in the decomposition of A -(i-butyl)-A -nitrosobenzamide ° ° and N-nitroso-7V-(l-phenylethyl)acetamide -in styrene and (4) no difference in acetate yields is observed when A -nitroso-A-(1-phenyl-ethyl) acetamide is decomposed in benzene in the presence or absence of 0-1 m Styrene and 1-phenylethyl acetate react with... 

Figure 24 Total ion chromatograms of washing powder. (A) SAFE versus (B) SDE. Key 1, Prenyl acetate 2, cw-3-Hexenyl acetate 3, 2-terL-Butylcyclohexyl acetate (cis-Agrumex) 4, 2-tert.-Butylcyclohexyl acetate (trans-Agnunex) 5, 1-Phenylethyl acetate 6, Geranyl acetate 7, Verdyl acetate.

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