J»-Nitrostyrene

Solid-state synthesis of /J-nitrostyrenes has been reported by Varma et al. in a process that uses readily available styrene and its substituted derivatives and inexpensive clay-supported nitrate salts, clayfen and clayan (Scheme 6.50) [170], In a simple experiment, admixed styrene with clayfen or clayan is irradiated in a MW oven (-100-110 °C, 3 min) or heated in an oil bath (-100-110 °C, 15 min). For clayan intermittent heating is recommended with 30-s intervals to maintain the temperature below 60-70 °C. Remarkably, the reaction proceeds only in solid state and leads to the formation of polymeric products in organic solvent. 

Scheme 6.50 Preparation /J-nitrostyrenes using clay-supported nitrate salts.

Reaction of 1-azidoadamantane with nitro and sulfoxy olefins (Scheme 77, R = H or Ph and X = N02 R = Ph and X = SOPh) leads directly to the triazoles two isomers are obtained from the /i-nitrostyrene reaction with the 5-phenyl-1-adamantyltriazole as the major product.155 Likewise, triazoles are the only products formed in the reaction of aryl azides with /J-nitrostyrene (Scheme 77)294,295 however, unlike the azidoadamantane reaction, a... 

Monomers with electron withdrawing groups are polymerized by phosphines (acrylic and methacrylic esters, acrolein, methyl vinyl ketone, /J-nitrostyrene, nitro-ethylene, acrylonitrile), whereas the phosphines have no effect on monomers more susceptible to acid catalysts (isobutylene, styrene). 

The reactivity of the halide ions could not be evaluated directly since they have not been studied with the same substrate. However, -toluene-thiolate ion is nine orders of magnitude more reactive than chloride ion towards 2-chloro-l,l-diarylethylenes in dimethylformamide. Although comparison may not be justified (see below), a similar reactivity ratio exists for the reactions of j8-bromo-j -nitrostyrene with iodide ion in butyl cellosolve and thiophenoxide ion in methanol. Bromide ion is 0-6 times as reactive as chloride ion towards l-anisyl-l-phenyl-2-chloroethylene. These relative reactivities of the halide ions should be regarded only as rough estimates. Their very low reactivity is also shown by the chloride exchange in ethyl /3-chlorocrotonate, which is at least 106 times slower than the substitution by thioethoxide ion (Jones et al., 1960) while trichloroethylene does not exchange at all even at 245° (Bantysh et al., 1962). 

Good asymmetric induction is observed in addition reactions when an optically active amine is used as the chiral catalyst. For example, the addition of thiols to /J-nitrostyrene carried out in the presence of various cinchona alkaloids gives chiral sulfides 7. ... 

It is noteworthy that the PhS /MeO rate ratios are not much different for the unreactive j3-bromo-j -nitrostyrene and its very reactive 2,4-dinitro analogue, being 4000 and 13,000, respectively. 

Similarly, /j-nitrostyrene (60) reacted with 1-dimethylamino-l-alkylbuta-dienes to afford phenylnitrocyclohexenes [55] (Equation 2.21) regioselectively and stereoselectively. 

A simple entry towards bi-and tricyclic N-oxy-/ -lactams by high pressure promoted tandem [4 + 2]/[3 + 2] cycloadditions of enol ethers and /J-nitrostyrene [65]... 

J-Nitrostyrene gives a 50 50 mixture of the two diastereomcrs with halomagnesium diallyldi-ethylalanate. 

Nitrostyrene (15a) can react as a dienophile in the Diels-Alder reaction with 2-alkoxy butadienes producing cyclic enol ethers (Scheme 9.23). By using an excess of nitrostyrene a domino reaction should take place with the in situ-generated enol ether. j -Nitrostyrene (15a) may react subsequently as a dienophile in the Diels-Alder reaction with a 2-alkoxy butadiene, as a heterodiene in the inverse Diels-Alder reaction of alkoxy cyclohexene which is formed primarily, and as a di-substituted dipolarophile in the 1,3-dipolar cycioaddition of the nitronate formed in the inverse Diels-Alder reaction. 2-Methoxy-l,3-butadiene (61) was selected for the Diels-Alder reaction, since it reacted in a completely regioselective manner with nitroalkenes. 

Thiolacetic acid, then a little tri-n-butylamine added to a suspension of 3,4-niethylenedioxy-j -nitrostyrene in benzene, and allowed to stand overnight l-(3,4-methylenedioxyphenyl)-l-acetylthio-2-nitroethane. Y 75%. F. e. s. K. V. Bhat and W. G. McCarthy, J. Pharm. Sci. 53, 1545 (1964). 

The pseudonitrosite of cu-styryltrimethylsilane is decomposed by alcoholic hydroxide to furnish /J-nitrostyrene (46). Silicophilic attack is preferred to abstraction of the very active hydrogen alpha to the nitro group. 

Nitrostyrene [100-13-0] M 149.2, m 20.5-21°. Crystd from CHCl3/hexane. Purified by addition of MeOH to ppte the polymer, then crystd at -40° from MeOH. Also crystd from EtOH. [Bemasconi et al. J Am Chem Soc 108 4541 1986.]... 

The medil carbonyls FefCOij, RiufC0 i2, andRhjfCo, j arecadilysts for the deoxygenadon of o-nitrostyrenes tinder carbon monoxide pressure to give indole derivadves fEq. 10.59. ... 

This procedure has been used in the preparation of other nitrostyrenes in the following yields o-nitrostyrene (40%),2 / -nitrostyrene (41%),2 and 3-nitro-4-hydroxystyrene (60%).2 A better procedure for more volatile styrenes involves simultaneous decarboxylation and codistillation with quinoline from the reaction flask. This method has been used to prepare the following styrenes o-chlorostyrene (50%),3 4 m-chlorostyrene (65%),4 -chlorostyrene (51%),4 m-bromostyrene (47%),4 o-methoxystyrene (40%),4 -methoxystyrene (76%),4 m-cyano-styrene (51%),3 and j -formylstyrene (52%).9... 

Another way to construct alkenes is by the addition of carbon radicals to nitrostyrenes such as 5. Ching-Fa Yao of National Taiwan Normal University in Taipei has reported (J. Org. Chem. 2004,69, 3961) an extension of this work, generating the acyl radical from the aldehyde 6, cyclizing it to generate a new radical, then trapping that radical with 5 to give 7. This article includes an overview of the several ways of adding radicals to 5. 

Petri, A., Marconcini, P. and Salvadori, P. (2005) Efficient immobilization of epoxide hydrolase onto silica gel and use in the enantioselective hydrolysis of racemic para-nitrostyrene oxide. J. Mol. Catal. B Enzymatic, 32, 219. 

Wan, P Davis, M.J., and Teo, M.A. (1989) Photoaddition of water and alcohols to 3-nitrostyrenes. Structure-reactivity and solvent effects. Journal of Organic Chemistry, 54, 1354-1359. 

Phenyl azide reacts with /J-bromo-/ -nitrostyrene (76 Ar = Ph) to give 1,5-diphenyl-4-nitro-l,2,3-triazole (77 Ar = R = Ph).67 Similarly, bromonitro-styrenes and sodium azide give the nitrotriazoles 77 (R = H) [Eq. (24)].68... 

Wang W, Wang J, Li H (2005) Direct, highly enantioselective pyrrolidine sulfonamide catalyzed Michael addition of aldehydes to nitrostyrenes. Angew Chem Int Ed Engl 44 1369-1371... 

Hu, Y., Yu, J., Yang, S., Wang, J., and Yin, Y. 1999. Substitution reaction of nitro group on a-nitrostyrene by organozinc halides under microwave irradiation. Synthetic Communications, 29 1157-64. 

The ability to accept electrons from donors is particularly pronounced in acrylic acid derivatives [85] its alkyl esters [78, 87, 88], acrylonitrile [88], acrylamide, hydroxylacrylates [85], and further in styrenes substituted with an electronegative atom or group m-nitrostyrene, 2,6-dichlorostyrene [86], / -nitrostyrene [89] bicyclobutane-1-carbonitrile [89] lactones /J-propio-Iactone [85], sulfolactone vinyl ketones [87] unsaturated dicarboxylic acids and their derivatives diethyl fumarate, fumaronitrile [90], ROOC—N— N—COOR [86], cyclic anhydrides of diacids [91 ], particularly maleic anhydride [78, 92] ethylenes substituted with electronegative groups [93, 95]... 

Regenass U, Roesel JL, Lydon N. Sulfonylbenzoyl-nitrostyrenes Potential bisubstrate type inhibitors of the EGF-receptor tyrosine protein kinase. J. Med. Chem. 1991 34 2328-2337. 50. 

The kinetics of decompn into nitroform / -nitrostyrene were studied. The decompn was found to be subject to general base catalysis. Its expl props were not detd Refs 1)BciI - not found 2)J.Hinc L. A. 

Das, J. P., Sinha, P., Roy, S. A Nitro-Hunsdiecker Reaction From Unsaturated Carboxylic Acids to Nitrostyrenes and Nitroarenes. Org. 

The pH-independent reactions of /7-methoxystyrene oxide and of /7-nitrostyrene oxide have different mechanisms than those for reactions of styrene oxides without strongly electron-donating or strongly electron-withdrawing groups. Both of these compounds are much more reactive than predicted from a Hammett sigma-rho plot of log k0bsd versus a for the pH-independent reactions of styrene oxide and its p-methyl and p-chloro derivatives.41 The most likely explanation for the enhanced reactivity of /7-nitrostyrene oxide is that attack of water at the /j-carbon, which is... 

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