P-Nitrostyrene

The above are examples of the Claisen - Schmidt reaction. The formation of p-nitrostyrenes by reaction of nitroalkanes with aromatic aldehydes in the presence of aqueous alkali may be included under the Claisen- hmidt condensation ... 

It is of interest to note that reduction of p-nitrostyrene with lithium aluminium hydride (compare Section VI, 10) gives p-phenylethylamine CgHgCHjCHjNHj. 

Chapter IV. a-Chloromethylnaphthalene (IV,23) benzylamine (Gabriel synthesis) (IV,39) i r.N -dialkylanilines (from amines and trialkyl orthophosphates) (IV,42) a-naphthaldehyde (Sommelet reaction) (IV,120) a-phenyl-cinnamic acid (Perkin reaction using triethylamine) (IV,124) p-nitrostyrene (IV,129) p-bromonaphthalene and p naphthoic acid (from 2 naphthylamine-1 -sulphonic acid) (IV,62 and IV,164) diphenic acid (from phenanthrene) (IV,165). 

A two-step synthesis of indoles from o-nitrobenzaldehydes proceeds by condensation with nitromcthanc followed by reductive cyclization. Like the Leim-gruber Batcho method, the principal application of the reaction is to indoles with only carbocyclic substituents. The forniation of the o,p-dinitrostyrenes is usually done under classical Henry condensation conditions but KF/18-crown-6 in propanol was found to be an advantageous reaction medium for acetoxy-substituted compounds[1]. The o,p-dinitrostyrenes can also be obtained by nitration of p-nitrostyrenes[2]. 

Irans-P-Nitrostyrene [5153-67-3] M 149.2, m 60°. Crystd from absolute EtOH, or three times from benzene/pet ether (b 60-80°) (1 1). 

Figure 2.9. NMR spectra of 3,4-dimethoxy-p-methyl-p-nitrostyrene (9) [CDCI3, 25 C, 20 MHz], (a, b) H broadband decoupled, (a) complete spectrum with CH3 quartets at Sc = 14.1 and 56.0 (b, c) decoupled and coupled partial spectrum of benzenoid and alkene carbon atoms, (c) obtained by gated decoupling...

From the HH COSY contour plot 12a it can be established which cycloadduct has been produced from l-(iV,iV-dimethylamino)-2-methylbuta-1,3-diene and tra 5-P-nitrostyrene. The Jhh coupling constant in the one-dimensional H NMR spectrum 12b can be used to deduce the relative configuration of the adduct. 

Trimethylsilyloxy-p-nitrostyrene was the target of Knoevenagel condensation of 2-trimethyl-siloxybenzaldehyde with nitromethane in the presence of -butylamine as base. NMR spectra 20 were obtained from the product of the reaction. What has happened ... 

In the synthesis of chuangxinmycin, Kozikowsld et al. employed the potassium salt of the acid 23 to condense with DMFDMA 6 to obtain the P-nitrostyrene 24 with the... 

Coe et al. reported an efficient modification for the preparation of /-substituted indole analogs for biology screening in good yield. The intermediate P-nitrostyrene 44, prepared from the condensation of 43 with DMFDMA, underwent methanolysis and reduction to provide the aniline acetal intermediate 45. Alkylation of amine 45 was carried out employing standard conditions of reductive alkylation to provide A-alkyl analogs represented by 46. The indole 47 was generated by formation of the oxonium ion (from 46) under acidic conditions, followed by cyclization, accompanied by loss of methanol. 

The first reported electroorganic synthesis of a sizeable amount of material at a modified electrode, in 1982, was the reduction of 1,2-dihaloalkanes at p-nitrostyrene coated platinum electrodes to give alkenes. The preparation of stilbene was conducted on a 20 pmol scale with reported turnover numbers approaching 1 x 10. The idea of mediated electrochemistry has more frequently been pursued for inorganic electrode reactions, notably the reduction of oxygen which is of eminent importance for fuel cell cathodes Almost 20 contributions on oxygen reduction at modified... 

It is not surprising then that the first reported surface mediated reaction made use of vicinal dihalides. In addition to poly-p-nitrostyrene immobilized metallo-porphyrins and viologens were found to be catalytically active. Recently,... 

Using this crude mung bean preparation, the production of (R)-p-nitrostyrene oxide was achieved in 82% ee and 83.5% yield. After recrystallization, greater than 99% ee was achieved. 

Dipolar cycloaddition reactions of thioisoraunchnones (l,3-thiazolium-4-olates) have not been as extensively studied as those of munchnones (l,3-oxazolium-5-olates) despite offering rapid access to novel heterocyclic compounds. The cycloaddition of the thioisomunchnone (52) with trans-P-nitrostyrene results in the formation of two diastereoisomeric 4,5-dihydrothiophenes (53) and (54) via transient cycloadducts. These cycloadducts then undergo rearrangement under the reaction conditions <96JOC3738>. 

The direct conversion of styrene to P-nitrostyrene using clay doped with nitrate salts has been reported. Styrene and clayfen (iron nitrate on clay) or clayan (ammonium nitrate on clay) are mixed well and then heated at 100-110 °C in solid state to give P-nitrostyrene in 68% yield.551 A more simple one-pot synthesis of P-nitrostyrene from styrene has been reported P-nitrostyrene is prepared in 47% yield on treatment of styrene with CuO HBF4,12, andNaN02 in MeCN at room temperature.55b... 

The synthetic applications of this reagent to the synthesis of nitroalkenes have been known since the 1960s.60 Nitration of alkenes with nitryl iodide, generated in situ from iodine and silver nitrite, is convenient for the synthesis of P-nitrostyrenes with various functional groups.61 This method is applied to the synthesis of ortho-methoxylated phenylisopropylamines, which are potent serotonine agonists (Eq. 2.31).62... 

Various variants of this process are presented for pyrrole synthesis. For example, reactions of 1,3-dicarbonyl compounds with P-nitrostyrene followed by treatment with amines give 3-acylpyrroles (Eq. 10.5).7... 

Corey et al. investigated the kinetic isotopic effect (KIE) in asymmetric dihydroxylation. 12C/13C KIE was measured for the dihydroxylation of styrene, p-nitrostyrene, and 4-methoxy-benzoate (Figure 7).197 The observed similar 12C/13C isotopic effect of two olefinic carbons... 

The configurational average in eqn (10) can also be performed (8) with eqn (1). In table III we present the results of our calculations (8) of eqn (10) for poly(p-nitrostyrene) versus the tacticity of the polymer. No experimental EFSHG results have been reported for... 

Calculated for poly(p-nitrostyrene) at 25 "C versus tacticity Pr x - 200 repeat units... 

Teichmann, H., Thierfelder, W., and Weigt, A., P-functionalization of P-nitrostyrenes with trialkyl phosphites, /. Prakt. Chem., 319, 207, 1977. 

Our knowledge of crystallization mechanisms is still quite rudimentary. However, crystal strudures such as 3-nitro-4-hydroxy-p-nitrostyrene quinoxa-line and morellic acid provide snapshot views of some of the events that may occur during crystallization of more normal compounds. One attempts to get a better appredation of the dynamic processes that occur during crystallization events by studying crystal structures which though static as are all crystal structures, are still suggestive... 

P-nitrostyrenes, preparation by nitration of styrenes, 16 581 P-n-methylionone, 24 565 P-octaalkylporphyrins, 14 552 Betapace... 

Al-Nitrosodiethanolamine, 2 449, 450 Nitroso dyes, 9 263-264 Nitro soluble dyes, 7 373t Nitroso soluble dyes, 7 373t Nitrosomonas, use in recirculating aquaculture biofiltration, 3 196 P-Nitrostyrenes, preparation by nitration of styrenes, 16 581 Nitrosyl chloride, 20 634 Nitrosyl complexes, osmium, 19 642 Nitrosyl perchlorate, 18 279 Nitrosyl tetrafluoroborate, 4 144t n-Nitrotoluene, 17 263... 

The elimination of HBr from ds-yS-bromo-p-nitrostyrene [155] producing the acetylene [156], has been studied by Naso and Ronzini (1974) using KF as the base (25). Their results (Table 43) show that the rate enhancement due to the... 

Fluoride-promoted elimination of HBr from eis-/ -bromo-p-nitrostyrene [1551 under solid-liquid conditions ... 

Scheme 11. Deracemization of p-nitrostyrene oxide and application to the synthesis of (R)-nifenalol...

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