Formaldehyde → N-Benzyl trans-4,5-bis(hydroxymethyl)isoxazolidine

Beteiligte Stoffe

Reaktionsschritte

A mixture of N-benzylhydroxylamine (4.4 g, 27.7 mmol) and anhydrous NaOAc (3.0 g, 36.7 mmol) in 35 ml EtOH was stirred at ambient temperature for 15 min, after which time formaldehyde (4.1 ml, 55.1 mmol) was added and the mixture stirred for another 30 min. A solution of (E)-but-2-ene-1,4-diol (1.63 g, 18.50 mmol) in ethanol (20 ml) was then introduced to the mixture in a single slug and the resulting solution refluxed for 18 hours. The mixture was cooled, concentrated and taken up in DCM and the solution washed sodium bicarbonate solution, dried and concentrated to an immobile oil (5.25 g). The crude product was fractionated by chromatography over silica eluting firstly with EtOAc and then with 5% MeOH/EtOAc and the title compound was isolated as an immobile syrup (1.95 g). The chromatography was repeated with only EtOAc as eluant and the compound isolated (1.46 g, 35%) as an homogeneous syrup. 1H NMR (CDCl3) δ 7.41-7.22 (m, 5H), 4.10-3.82 (m, 2H), 3.80-3.60 (m, 4H), 3.5-2.3 (m, 5H). 13C NMR 137.0, 129.3, 128.8, 128.0, 81.6, 64.1, 63.0, 58.7, 47.7.

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