3-Tert-butyl-1,2-oxazol-5-amine → N-(3-tert-Butyl-isoxazol-5-yl)-2-(4-chlorobenzenesulfonyl)-4-hydroxy-2-methyl-butyramide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 3-tert-butyl-isoxazol-5-ylamine (0.421 g; 3.00 mmol) in methylene chloride (5 mL) was added dropwise trimethylaluminum (1.5 mL of a 2.0 M solution in toluene; 3.00 mmol). The mixture was stirred 15 minutes and 3-(4-chloro-benzenesulfonyl)-3-methyl-dihydro-furan-2-one (0.659 g; 2.40 mmol) added. The mixture was stirred 3 hours, heated to 45° C. for approximately 40 hours, cooled to room temperature and carefully quenched with 10% aqueous citric acid, aqueous sodium tartrate and chloroform. The organic layer was dried (MgSO4). Removal of the volatiles in vacuo provided a residue which was purified by silica gel chromatography using ethyl acetate and hexanes as the eluent. Removal of the volatiles from the product-rich fractions provided 0.616 g of the desired product. 1H NMR (CDCl3) δ 9.85 (bs, 1H), 7.75 (d, 2H), 7.55 (d, 2H), 6.24 (s, 1H), 3.97 (m, 1H), 3.85 (m, 1H), 2.62 (m, 1H), 2.32 (m, 1H), 1.65 (s, 3H), 1.32 (s, 9H). MS (ESI): m/e 415, 417 (M+H).

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