3- Phenylpentan

Eriedel-Crafts alkylation of ben2ene with isomeric amyl alcohols proceeds with some rearrangement. Eor example, both 2- and 3-pentanol gave the identical product mixture (60% 2-phenylpentane, 31% 3-phenylpentane, and 9% / f/-pentylben2ene) from reaction with ben2ene in the presence of BE catalyst (85). 

In the presence of alkah metals such as potassium and sodium, toluene is alkylated with ethylene on the methyl group to yield, successively, normal propylbenzene, 3-phenylpentane, and S-ethji-S-phenylpentane (21). 

Et2Zn also participates in the reductive coupling as a formal hydride source. Results for the Ni-catalyzed, Et2Zn-promoted homoallylation of carbonyl compounds with isoprene are summarized in Table 7 [30]. Et2Zn is so reactive that for the reaction with reactive aromatic aldehydes it causes direct ethylation of aldehydes, and the yields of homoallylation are diminished (runs 1 and 2). Unsaturated aldehydes seem to be subject to the Michael addition of Et2Zn. Accordingly, for the reaction with cinnamaldehyde, none of the expected homoallylation product is produced instead, the 1,4-addition product of Et2Zn, 3-phenylpentanal is produced exclusively (run 3). 

Note According to Chevron Phillips Company s (2006) Technical Data Sheet, >99 wt % propyl-benzene typically contains 3-phenylpentane (< 1.0 wt %), indan (< 0.5 wt %), and isopropylbenzene (<0.15 wt %). 

Phenylpentane, see Propylbenzene Phenylphenol, see 2-Chlorobiphenvl 2-Phenylpropionaldehyde, see Isopropylbenzene Phenylpyruvic acid, see Biphenyl l-Phenyl-3-(l,2,5-thiadiazol-3-yl)urea, see... 

Of the olefins, ethylene has been most extensively studied (19, 21, 23-26, 36) it reacts most readily in base-catalyzed alkylations. In general temperatures of 150-200 are used with relatively low ethylene pressures (0-70 atm.). Benzylic hydrogens are replaced by ethyl groups i.e., toluene yields n-propylbenzene. Additional substitution on the a-carbon may yield 3-phenylpentane and 3-ethyl-3-phenylpentane [Reaction (3)]. 

The main reaction product, 2-phenylbutane, shows no detectable optical activity between 590 and 350 m. The 2-phenylbutane does not arise from the alkylcobalt carbonyls as reported (10) since these give rise to the optically active 3-phenylpentanal or 4-phenylpentanal. Taking into account the peculiar behavior under oxo conditions of double bonds conjugated with phenyl rings (14), it might be assumed that electronic effects produce predominately the disubstituted benzylcobalt complex CH3... 

Consider an example using an ester. When an excess of ethylmagnesium bromide is added to methyl benzoate, the first equivalent adds and methoxide is expelled, giving propiophenone. Addition of a second equivalent, followed by protonation, gives a tertiary alcohol 3-phenylpentan-3-ol. 

A material such as Na°/NaY catalyzes the aldol condensation of acetone, to form mesityl oxide and eventually isophorone. Another strong base catalyzed reaction is the side chain alkylation of toluene with ethylene. In contrast with acid catalysis, side chain reaction is strongly preferred over ring alkylation. With a Na°/NaX in the gas phase at 473 K, toluene reacts to give n-propylbenzene (66%) and the dialkylated product, 3-phenylpentane (32%) (41). 

Moreover, the synthesis and good stability of the covalent carbon-bismuth compound in the case of acetone, 2-oxopropyltriphenylbismuthonium perchlorate, excluded this type of intermediate as a common pathway, although this view was questioned by Suzuki et The reaction of the sodium salt of acetylacetone with triphenylbismuth dichloride led to a bismuthonium salt (37) decomposing slowly at room temperature to give eventually 3-phenylpentane-2,4-dione (35). ... 

The attempt to substitute the thallium moiety of phenylthallium diacetate with acetylacetone failed to give the 3-phenylpentan-2,4-dione. Instead, the presence of the disproportionation product (120) of the thallium reagent was detected by... 

A solution of acetylacetone (0.15 g, 1.5 mmol) in anhydrous benzene or dichloromethane (7.5 ml) was stirred under argon in the presence of triphenylbismuth carbonate (1.9 g, 3.8 mmol) until the reaction is complete. The reaction mixture was filtered though Celite, the filtrate was evaporated, and the residue was purified by preparative thick layer chromatography or column chromatography to give 3-phenylpentane-2,4-dione (0.10 g, 38% yield) and 3,3-diphenylpen-tane-2,4-dione (0.15 g, 40% yield) [85JCS(P1)2667]. 

Ranby et have also used model compounds such as 3-phenylpentane for investigating the mechanisms of photo-oxidation of polystyrene. The photooxidation of polystyrene has been investigated in solution by a number of workers. Woolinski has observed the development of unsaturation and implicated the involvement of singlet oxygen in the mechanism of photo-oxidation, whereas Easton and MacCallum " invoke the involvement of polymer-solvent complexes in initiation. The photo-oxidation of polystyrene has been found to have a kinetic chain length of 10 —... 

Cram and Dalton (//) have observed that reaction of t/ireo-2-phenyl-3-pentyl methanesulfonate (33) with potassium in 1,2-dimethoxyethane gave a hydrocarbon product containing 94% of 2-phenylpentane and 6% of 3-phenylpentane (product of phenyl migration). 

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