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urri

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  1. - Даже у Айседоры Дункан, - звонко крикнула женщина.
  2. Из аминокислоты навряд ли,можно из ее эфира,но выход очень слабенький
  3. urri

    Фенилэтиловый спирт

    Step 1 Synthesis of 2-(4-nitrophenyl)ethyl nitrate. To 250 ml of HNO3 at -10 to -5°C under vigorous stirring was added dropwise 61.08 g (0.450 mol) of β-phenethyl alcohol; last few ml of β-phenethyl alcohol was added at 10°C. After the end of the nitration, the reaction mixture was poured with stirring into 3 l of ice-water. After standing the mixture, the dilute acid was decanted from a heavy yellow liquid which was then repeatedly washed with water. Yield of crude nitration products was 102.77 g (96.9%). Nitro compounds were kept at -21°Cto complete crystallization, the crystalline mass was then pressed on a vacuum filter to separate liquid o-isomer. The crystalline substance was then washed twice with ethanol and thoroughly separated by pressing from the residual 2-(2-nitrophenyl)ethyl nitrate which is insoluble in alcohol. After drying in air was obtained 46.26 g of crude 2-(4-nitrophenyl)ethyl nitrate, which was then recrystallized from ethanol. Ethanol was removed under vacuum from the filtrate remaining after the separation of o-isomer, the residue was kept at -21°C for several days and then from the crystallized precipitate was isolated 8.9 g of 2-(4-nitrophenyl)ethyl nitrate. The yield of pure 2-(4-nitrophenyl)ethyl nitrate 37.73 g (35.6%), a needle with a slight greenish-yellow tinge. The total yield of crude product was 55.34 g (52.2%). mp 54-55°C Step 2 Synthesis of 2-(4-aminophenyl)ethanol. To a solution of 1.28 g (0.2048 mol) of 2-(4-nitrophenyl)-ethyl nitrate in 260 ml of methanol was added NiRe prepared from 1.0 g of Ni-Al alloy, then 25 ml of N2H4·H2O was added and the mixture was stirred till exothermic reaction began. When the reaction intensity decreased, to the reaction mixture was added another 25 ml portion of N2H4·H2O, the mixture was heated in a water bath to initiation of a violent reaction. After decomposition of most of the hydrazine, to the mixture was added 17 ml of N2H4·H2O and the reaction mixture was heated at 80°Cuntil the reaction completion and then kept at 40-45°C to complete cessation of gas evolution. Then catalyst was removed from warm solution by filtration, volatiles were distilled off by heating under vacuum in a rotary evaporator. To the liquid residue was added 50 ml of absolute ethanol, the solvent was distilled off and the residual suspension was left for crystallization. The crystals were filtered off from the mother liquor, washed with absolute ethanol and after drying in vacuum over P4O10 was obtained 9.83 g of 2-(4-aminophenyl)ethanol as white crystals. The filtrate was evaporated in a vacuum, the residue was poured onto a petri dish and after the evaporation of volatile components, the substance was rubbed on the filter with a small amount of absolute ethanol. After filtration, the precipitate was washed with absolute ethanol and dried in air. As a result, 5.26 g of a white finely crystalline substance was obtained. Total yield 15.09 g (83%). mp 105°C 1H NMR spectrum, δ, ppm: 2.613, 2.632, 2.650 m (2H, CH2), 3.598, 3.617, 3,635 m (2H, CH2O), 6.593, 6.599, 6.604, 6.615, 6.620, 6.627 (2H, 2,6-Ar), 6.899, 6.906, 6.910, 6.922, 6.926, 6.933 (2H, 3,5-Ar).
  4. В 'Препаративной химии индола' Жунгиету,кажется,там с тионилом пропись
  5. urri

    Синтез дициана.

    С P2O5 можно получить
  6. А какой конкретно альдегид?
  7. Не фенилгидразин в схеме,фенилгидроксиламин
  8. urri

    Индол

    Выкрутились...
  9. urri

    Индол

    Вы понимаете, что могут существовать хиральные структуры без хиральных атомов? Считаю,что на этом аргументе в нашей дискуссии можно поставить точку.
  10. urri

    Индол

    Под сутью дела я понимаю вопрос о возможной хиральности данной структуры и тут никаких разночтений быть не может-она ахиральна вне зависимости от чьего-либо личного мнения.В основе-ароматический карбазол(Вы же не станете утверждать,что он хирален?),а заместители вполне обычные,советую отвлечься от медицинских терминов и ,включив пространственное воображение,представить себе молекулу попроще- 5-бромо-1,3-бензодиоксол к примеру,получите полную аналогию.
  11. urri

    Индол

    Коллега, при чём тут карбазол? Вы о чём, вообще, говорите? Фурокарбазол,если точне,можно и совсем номенклатурно назвать,но сути дела это не меняет
  12. urri

    Индол

    Вообразить хиральный карбазол?
  13. urri

    Индол

    Хиральным такой продукт быть не может,по очевидной причине.
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