Восстановление нитропропенов в две стадии через нитропропан.

Примечание - в этом случае нитропропен сначала восстанавливается в нитропропан борогидридом натрия, но нитропропены восстанавливаются в нитропропаны массой известных способов - например, цинковой пылью в солянке (аналогично восстановлению нитростиролов цинковой пылью).

1) An oven-dried 250ml rb flask sitting in an ice/salt bath is charged with 50ml IPA (dried w/ MgSO4), 1g 8-20 mesh indicating silica gel and 80mmol NaBH4 (3g) with mag stirring. When temp of solution was 0°C a solution of 20mmol of desiccated TMP2NP (5g) in 100ml dry THF, is added dropwise from a pressure equalized addition funnel over 1.5 hours. Rxn is allowed to stir for an additional 0.5 hours, until all traces of orange had disappeared. Ice bath is removed and rxn mixture was vacuum filtered and the solvent stripped off using low vac on a water bath.

2) 150ml MeOH is added to the residue followed by the slow addition of 320mmol GAA (19g) from a pressure equalized addition funnel vented by a hose out of doors. The funnel is removed and 15ml dH2O is added with 50mg HgCl2. With vigourous mag stirring 0.5 moles Al (13.4g) (regular reynolds wrap) is slowly added over a 2 hour period and allowed to stir an additional hour while remaining Al goes into suspension. Rxn is transferred to a 500ml erlenmeyer flask and slowly basified with 50% NaOH. When rxn with remaining Al has subsided, it is a viscous gel. Flask is stopped and shaken until the gel breaks down into a fluid again. It is then extracted 2X with 100ml toulene. Extracts pooled and washed 1X w/ Saturated NaCl soltion, 1x w/ dH2O, dryed over MgSO4. Then pre-gassed aliquots of toulene are added with filtration between aliquots until no more crystals precipitate.

Yield: 11mmol TMA2.HCl (2.75g) 55% molar yield

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