Co- Nitrostyrene

If the nitro group is located at the ethylene fragment, one-electron transfer initiates dimerization of the developing anion-radicals. a-Nitrostilbene, w-methyl-co-nitrostyrene, and a-nitro-p-ferrocenylethylene give anion-radicals, which dimerize spontaneously. It is interesting to compare reactions of cyclooctatetraene dipotassium (C8HgK2) with a-nitro and a-cyano ferrocenylethylenes (Todres and Tsvetkova 1987, Todres and Ermekov 1989 Scheme 3.4). 

The nitroaldol may be dehydrated to a nitroalkene in the case of nitroaldols arising from aromatic aldehydes this dehydration reaction occurs spontaneously as is illustrated in the preparation of co-nitrostyrene (Expt 6.136). The nitroalkenes are important dienophiles in the Diels-Alder reaction (Section 7.6, p. 1117). An example of the Michael addition reaction is illustrated in the syn-... 

Cognate preparations. 3,4-Methylenedioxy-co-nitrostyrene. In a 250-ml round-bottomed flask mix 30 g (0.20 mol) of 3,4-methylenedioxybenzalde-hyde (piperonal), 13.4g (0.22mol) of nitromethane, 7.8g (0.1 mol) of ammonium acetate and 50 ml of glacial acid. Attach a reflux condenser, and boil the mixture under gentle reflux for 1 hour. Pour the reaction mixture with stirring into a large excess of ice-water (about 1 litre). When all the ice has... 

This reaction is carried out using the steel pressure vessel and techniques described in Section 2.17.2, p. 97. To the dry pressure vessel add 7.46 g (0.05 mol) of co-nitrostyrene (Expt 6.136), about 0.1 g of hydroquinone (a polymerisation inhibitor) and 15 ml of dry toluene. Fit a rubber bung carrying a calcium chloride guard-tube and cool the vessel to — 78 °C in an acetone-Cardice bath. During the cooling process set up the acetone-Cardice... 

The formation of co-nitrostyrenes (illustrated in Expt 6.136) by reaction of nitroalkanes with aromatic aldehydes in the presence of aqueous alkali may be classified with reactions of the Claisen-Schmidt type. 

A new preparation " of the diamine (7), by Michael addition of dimethyl-acetamide to 2,5-dimethoxy-co-nitrostyrene followed by reduction of the adduct, constitutes a new synthesis of bufotenine (Scheme 1), since the amine (7) has already been converted into bufotenine. 

Dimethoxybenzaldehyde, nitromethane, and alcoholic potassium hydroxide solution give the derived a-nitro alcohol if the reaction mixture is later acidified with 50% acetic acid however, acidification with N-sulfuric acid affords 2,3-dimethoxy-co-nitrostyrene (93 % yield) directly.975... 

Most of these reactions only can take place under acidic medium. If the R group is an aromatic group, with an organic amine as catalyst, the reaction can take place with product of co-nitrostyrene. 

Bromo-co-nitrostyrene and cyclohexane-l,3-dione kept 40 hrs. at 0° inmethanolic Na-methoxide 3-(4-bromophenyl)-2-hydroximino-6,7-dihydro-4(5H)-benzofura-... 

A comprehensive comparison among different expressions was done by Koutek, in a remarkable paper of the late 1970s [201] on the basis of the data available for 9 compounds, viz. carbazole, indole, l,3-diphenyl-2-pyrazoline, (hexamethyl-benzene + tetrachlorophthalic anhydride) CT-complex, 4-amino-4 -nitrostilbene, 4-dimethylamino-benzonitrile, 4-dimethylamino-4 -nitrostilbene, 4-dimethylamino-co-nitrostyrene, and 4-dimethylamino-benzylidene-4 -nitroaniline. Unfortunately, the analysis was limited to neutral molecules characterised by the presence of a symmetry axis, or at least by expected co-directional electric dipole moment vectors. 

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