Methyl-l-phenylpropane

Phenylacetonitriles can be induced to undergo Michael reactions with unactivated alkenes. For example, propenylarenes, formed in situ from allylarenes, react with phenylacetonitriles to form 3-aryl-l-cyano-2-methyl-l-phenylpropanes (70-98%) [3] by a procedure analogous to 6.4.1.B, Similarly, the nitriles react with alkynes giving allyl cyanides (80-95%) [38]. 

Synonyms BRN 1852218 i-BuBz -Butylbenzene EINECS 208-706-2 IsoBuBz (2-Methyl-propyl)benzene 2-Methyl-l-phenylpropane, NSC 24848 l-Phenyl-2-methylpropane UN 1993. 

Methyl-l-phenylpropane, see Isobutylbenzene 2-Methyl-2-phenylpropane, see ferf-Butylbenzene Methyl phthalate, see Dimethyl phthalate... 

The formation of different products is also observed in the diacylation of 2-methyl-1-phenylbut-l-ene (63TL91). When either the alkene or 2-methyl-l-phenylpropan-2-ol is treated with acetic anhydride in perchloric acid, 2,4,6-trimethyl-3-phenylpyrylium perchlorate is formed. However, the use of acetyl chloride and aluminum chloride as the acylating agent leads to the 4-benzyl-2,6-dimethylpyrylium salt, whilst benzoyl chloride gives 4-methyl-2,4,6-triphenylpyrylium perchlorate under similar conditions. 

Methyl-l -phenylpropan-1 -one Cyclopentyl phenyl ketone Cyclobutyl phenyl ketone Cyclopropyl phenyl ketone 4-Benzhydrylbenzophenone 9-Acetylfluorene... 

In l-amino-2-methyl-l-phenylpropane, for example, the C, C, C, of phenyl takes... 

HRP embedded monolith reactor. The HRP embedded monolith reactor was prepared by irradiating it with UV light (360 nm) for 30 min at room temperature with the mixture of 2-hydroxy-2-methyl-l-phenylpropan-l-one- 3-methacryloxy-propyl -trimethoxysilane, ripoxy SP-1507, sorbitan and horseradish peroxidase (HRP) in the Hematocrit glass tube. ... 

Hydroxy-2-methyl-l-phenylpropan-l-one, photoinitiator, 381 DC -704 Silicone oil, 229 DC -710 Silicone oil, 229 Denka SMI... 

In a 50-ml round-bottomed flask 5 g hexamethylene bisacrylate and 0.2 g of 2-hydroxy-2-methyl-l-phenylpropane-l-one as a photoinitiator are stirred tmtil a homogeneous solution is obtained. The flask is evacuated for a short time to remove bubbles from the solution. An IR spectmm is taken of the homogeneous solution. 

Hydroxy-2-methyl-l-phenylpropane-l-one gives a reaction similar to that of Equation (1.80) and produces radicals by UV irradiation ... 

One example of UV nanoimprint resists is shown in Figure 4.9. The resin contains three kinds of acryl monomers t-butylacrylate, ethylene glycoldiac-rylate, and (3-acryloxypropyltristrimethylsiloxy)silane. The resist also contains a photoinitiator, 2-hydroxy-2-methyl-l-phenylpropane-l-on. The resin... 

Thus, a mixture of photoinitiator 2-hydroxy-2-methyl-l-phenylpropan-l-one (Ciba) and RAMEB in water was sonificated for 5 min 5delding a clear solution of the complexed initiator. To evaluate the influence of cyclodextrin, the polymerization of NIPAAm in aqueous solution initiated with complexed and imcom-plexed photoinitiator Ciba was performed. After the addition of 2 mol% of RAMEB-complexed Ciba, the mixture was irradiated with a high pressure mercury lamp at 20°C. UV spectroscopic measurements (Fig. 10) revealed that the polymerization reaction initiated with the RAMEB-complexed initiator is faster and ends up with higher yield than the pol5mierization in the absence of cyclodextrin (38). 

Fig. 10. UV absorbance of nonreacted NIPAAm during polymerization reactions initiated with 2-hydroxy-2-methyl-l-phenylpropan-l-one (Ciba) in the presence of qrclodextrin ( ) without cyclodextrin ( ).

Influence of wavelength. In a study of the response of a UV-curable composition to different irradiation wavelengths, 2-hydroxy-2-methyl-l-phenylpropan-l-one (Darocur 1173), at a concentration of 3% in an acrylate resin, was used as photoinitiator. The UV spectrum of the photoinitiator showed an absorption maximum at 320 nm, indicating that this should be the best wavelength for irradiation. The photocalorimetric measurements with monochromatic irradiation of the samples at a constant intensity indicate that the highest polymerisation rate occurs at an excitation wavelength of 340 nm. 

The reaction of various alkyl radicals with peroxides has attracted some interest. Thus the reactions of both the methyl radical and the hydroxymethyl radical with hydrogen peroxide and of the methyl radical with t-butyl hydroperoxide " have been reported and the rate constants for the processes determined. In related work it was reported that alkanes are iodinated by perfluoroalkyl iodides under free-radieal conditions (using r-BuOOH in AcOH) to give iodoalkanes. However, in the presence of excess r-BuOOH, the iodoalkanes were reduced back to the starting alkanes. The mechanism of 0—0 bond cleavage in 2-methyl-l-phenylpropan-2-yl hydroperoxide using iron(in) porphyrins has indicated that both homolytic and... 

Epoxy-l-methoxy-2-methyl-l-phenylpropane refluxed 17 hrs. with excess piperidine a-piperidinoisobutyrophenone. Y 91.5%. F. e. and limitations s. G. L. Stevens and G. Hung Ghang, J. Org. Ghem. 27, 4392 (1962). 

Outline a synthesis of 2-methyl-l-phenylpropane (iso-butylbenzene) starting from benzene using a Friedel-Crafts reaction. Answer Friedel—Crafts acylation followed by Clemmensen reduction. 

Apparently, in both mechanisms the steric factors are important to explain the relative reaction rates observed for the different substrates. At this point we should study in detail the remaining data, starting with the differences observed in die rates of debromination of l,2-dibromo-2-methyl-l-phenylpropane 11 and 1,2-dibromodecane 12. 

Let us consider whether Mechanism 2 could justify the differences in reaction rates between 11 and 12. We should remember that the stability of a bromonium ion not only depends on steric factors but, like carbocations, they are very sensitive to the presence of substituents able to stabilize the positive charge (i.e. a phenyl group). This could explain why l,2-dibromo-2-methyl-l-phenylpropane 11 reacts 330 times faster than 1,2-dibromodecane 12. The bromonium ion intermediates obtained from 11 and 12 are represented in Scheme 29.9. Although intermediate 15 is more crowded than intermediate 16, the presence of a phenyl group should make it far more stable. In consequence, the debromination of 12, has to be considerably slower. 

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