1 - -1 phenylethylene

In a 250 ml. distilling flask (1) place 122 g. (119 ml.) of p-phenylethyl alcohol and 40 g. of sodium hydroxide peUets (or 56 g. of potassium hydroxide). Heat is evolved. Warm gently until bubbles commence to form and the mixture separates into two sharply-defined layers. Distil slowly water, etc. passes over first accompamed by the gradual dis appearance of the upper phase. FinaUy the styrene passes over at 140 160° (mainly 150°) coUect this separately in a receiver containing about 0 1 g. of hydroquinone. Dry the distillate with a httle anhydrous calcium chloride or magnesium sulphate, and then distil under reduced pressure (2). C oUect the pure styrene at 42-43°/18 mm. The 3rield is 80 g. Add about 0-2 g. of hydroquinone (anti-oxidant) if it is desired to keep the phenylethylene. 

Phenylethylene boils at 145-146° at atmospheric pressure, but the high temperature causes a considerable loss by polymerisation. It has been stated that the addition of about 0-1 per cent, by weight of hydroquinone considerably reduces the extent of polymerisation at atmospheric pressure. 

Btamp/e Another example of frontier orbital theory uses the reaction of phenyl-butadiene with phenylethylene. This reaction is a [4 + 2] pericyclic addition to form a six-membered ring. It could proceed with the two phenyl rings close to each other (head to head) or further away from each other (head to tail). 

The LUMO of phenylethylene also has most density at the terminal (beta) carbon, so that these two atoms attach to each other, yielding the sterically unfavorable product. 

Styrene [100-42-5] (phenylethene, viaylben2ene, phenylethylene, styrol, cinnamene), CgH5CH=CH2, is the simplest and by far the most important member of a series of aromatic monomers. Also known commercially as styrene monomer (SM), styrene is produced in large quantities for polymerization. It is a versatile monomer extensively used for the manufacture of plastics, including crystalline polystyrene, mbber-modifted impact polystyrene, expandable polystyrene, acrylonitrile—butadiene—styrene copolymer (ABS), styrene—acrylonitrile resins (SAN), styrene—butadiene latex, styrene—butadiene mbber (qv) (SBR), and unsaturated polyester resins (see Acrylonithile polya rs Styrene plastics). 

Esters can be obtained from halogenated olefins using a metal carbonyl catalyst (87), eg, /n j -l-bromo-2-phenylethylene is treated with nickel carbonyl in the presence of methanol to afford the corresponding methyl cinnamate (see Cinnamic acid). 

The mechanism of the reaction is unknown. The stereospecificity observed with (E)- and (Z)-l-methyl-2-phenylethylene points to a one-step reaction. The very low Hammett constant, -0.43, determined with phenylethylenes substituted in the benzene ring, excludes polar intermediates. Yields of only a few percent are obtained in the reaction of aliphatic alkenes with (52). In the reaction of cyclohexene with (52), further amination of the aziridine to aminoaziridine (99) is observed. Instead of diphenylazirine, diphenylacetonitrile (100) is formed from diphenylacetylene by NH uptake from (52) and phenyl migration. 

The rarely used systematie lUPAC name for polystyrene is poly-(1 -phenylethylene). 

Phenylethylene, see Styrene, monomer Phenyl glycidyl ether (PGE) 1 6.1... 

Styrene, monomer (phenylethylene) Succinaldehyde, see Glutaraldehyde Sucrose... 

Chemical Designations - Synonyms Isopropenylbenzene 1-Methyl-1-phenylethylene ... 

Chemical Designations - Synonyms Phenethylene Phenylethylene Styrol Styrolene Vinylbenzene Chemical Formula C6HjCH=CH2. 

Treatment of i-bromo-2-deuterio-2-phenylethane with strong base leads to a mixture of deuteruted and nondeuterated phenylethylenes in an approximately 7 1 ratio. Explain. 

An anti-oxygen such as catechol or hydroquinone is used to prevent polymerization. Hydroquinone should be added in the ratio of one part per thousand unless the phenylethylene is to be used immediately.1... 

Phenylethylene should not be distilled under atmospheric pressure since the temperature (146°) required for the distillation causes a considerable loss by polymerization. The decomposition of cinnamic acid cannot be effected by distillation under diminished pressure, since the acid under these conditions distils below the temperature required for decomposition (approxi-natcly 300°). 

Common chemistries include tannins and lignins but also more modem polyacrylates and derivatives, which often act as carriers for specific functional groups and provide novel chemistry molecules. The polyacrylates may also be copolymerized, perhaps with maleates [maleic anhydride, cis-butenedioic anhydride (OCOCHrCHCO) is the usual starting point material], styrene (vinylbenzene, phenylethylene,... 

The reaction of organolithium reagents is rapid and complete in less than 1 min even at low temperature, while Grignard reagents require 12-24h at room temperature to react completely. Treatment of ( )- or (Z)-l-methylsulfonyl-2-phenylethylene with trialkylbo-ranes yields exclusively ( )-olefins via a vinyl radical intermediate14. 

When ( )-l-methylsulfonyl-2-phenylethylene (105) was allowed to react with a-lithio-nitriles (106) in THF at — 60 to — 70 °C and then under reflux, 3-oxothiane 1,1-dioxides (107) were obtained in good yield, and no cyclopropanes were formed (equation 86)71. On the other hand, a-lithiophenylacetonitrile (106, R1 =Ph) reacted with 105 to give the cyclopropane 108 in good yield. Yields obtained in this cyclization are listed in Table 9 (equation 87)71. 

For phenylethylene, in which a double bond conjugated with a benzene ring permits struc-... 

The quantum-mechanical treatment previously applied to benzene, naphthalene, and the hydrocarbon free radicals is used in the calculation of extra resonance energy of conjugation in systems of double bonds, the dihydro-naphthalenes and dihydroanthracenes, phenylethylene, stilbene, isostilbene, triphenylethylene, tetraphenylethyl-... 

The secular equation for phenylethylene, in which a phenyl group is conjugated with a double bond, is the same as for 1,2-dihydro-naphthalene, and leads to the same value for the resonance energy. 

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