Восстановление нитростиролов алюминиевой амальгамой.

Эта реакция опробована на практике испанским юхимиком по имени СанЛайт, тем самым СанЛайтом, что впервые практически подтвердил возможность восстановления 2,5-диМеО-НС цинком в соляной кислоте.

Метод этот быстрый и грязный, его единственный, но огромный недостаток состоит в смешном выходе - всего 30-35% (хотя для восстановления нитроалканов - например, после восстановления двойной связи борогидридом натрия, а также для восстановления нитроспиртов, он даёт весьма высокие выходы, по отзывам практиков)

Как бы то ни было, вот он:

I made a mix of 11 grams of thick aluminium (from a tart recipier) cut in small pieces about 2x10mm, and 9 grams of noraml kitchen aluminium foil in 2x2cm. In the other hand, warmed 100ml of 96% ethanol and 100ml of acetic acid couldn't dissolve 10 g nitrostyrene. Addition of 30ml of water precipitated more nitrostyrene. Aluminium was amalgamated a la Shulgin. The warmed suspension was poured in the flask containing the aluminium amalgam, and immediatly started a super exhotermic reaction that thrown out some solution and aluminium. The ethanol was boiling, and there was also a lot of acetic acid smell. I thought I lost the reaction, but in five minutes, the rxn could be controlled with cold water. More alcohol was added, but a part of product was lost. Temp was about 60-80шC. Sometimes the rxn was heated a bit in warm water to activate it. A great part of aluminium didn't react.

Next day I made one of the worst workups ever in this kind of rxns. While filtering, 600 ml of water tap came into the flask. I washed the cake with water because the amine was in the acetate form (yes, sure), so I ended with more than 1 liter of solution. To avoid amine losts, H2SO4 was added and the solution concentrated till 150 ml, washed, basified and extracted (Aluminium hydroxides appeared and made the things more difficult). Evaporating of the solvent gave the characteristic fish-like smell of amines, and as the solvent was evaporated, the amine carbonate appeared (Yes, 2C-H carbonate). I converted it to the sulphate salt, because sulphate is probably less soluble than hydrochloride (easier to purify) and easier to make. To the brown amine salt, the solution was added dropwise to a 50% ethanolic solution of H2SO4. Crystals began to form, whereupon I added acetone and filtered and washed with acetone three times to give 2.4 grams of yelloish 2C-H sulphate. Having errors and hazards, not really bad. Probably the best work up is the classical one, basify, filter ... But doing things properly this one may be is not bad, and the main problem was that a bit of product was thrown out and the aluminium want react completely, may be is better to keep HgCl2 in the reaction, as in the recipe I have based this redcution, given at the Hive.

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