Sodium Azide → 2-Benzyloxymethyl-2-azido-1-phthalimido-ethane

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Reaction Steps

2-Benzyloxymethyl-2-(trifluoromethylsulfonyloxy)-1-phthalimido-ethane (8.5 g, 19.1 mmol) and sodium azide (2.5 g, 38.2 mmol) were stirred in dimethylformamide (80 ml) at 60° C. for 6 hours Under nitrogen. TLC in several systems was inconclusive because the Rf of the product was identical to the Rf of the starting material. A small sample was worked up and IR indicated full conversion to the azide. The reaction mixture was transferred to a 1 l extraction funnel and distributed between ethyl acetate (350 ml) and water (130 ml). The aqueous phase was extracted with ethyl acetate (80 ml); the combined organic phases were washed with water (2×120 ml), dried over magnesium sulphate, filtered and concentrated in vacuo to a pale brown oil. Crystallisation was initiated by adding ether (7 ml). Crystals were collected on a glass sinter, washed with cold ether and dried under vacuum for 28 hours. Yield: 4.5 g (70%). The mother liquors were concentrated, diluted with ether and seeded with crystals from the first crop--yielding another 1 g. Total yield: 5.5 g (85%). The structure was confirmed by NMR and IR.

Provenance & Evidence