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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 3-tert-butyl-isoxazol-5-ylamine (0.421 g; 3.00 mmol) in methylene chloride (10 mL) was added dropwise the trimethylaluminum (1.50 mL of a 2.0 M solution in toluene; 3.0 mmol). The mixture was stirred 15 minutes and 3-methyl-3-(tetrahydro-pyran-4-sulfonyl)-dihydro-furan-2-one (0.596 g; 2.40 mmol) was added. The mixture was heated to 45° C. overnight, cooled to room temperature, carefully quenched with 0.5 mL methanol, applied to a plug of silica gel and eluted with ethyl acetate. Removal of the volatiles in vacuo provided a residue which was purified by silica gel chromatography using ethyl acetate and hexanes as the eluent. The product-rich fractions were concentrated in vacuo to provide 0.646 g of the desired product. 1H NMR (CDCl3) δ 9.92 (bs, 1H), 6.29 (s, 1H), 4.11-3.92 (m, 4H), 3.86 (m, 1H), 3.60 (m, 1H), 3.40 (m, 2H), 2.57 (m, 1H), 2.36 (m, 1H), 2.12-1.90 (m, 4H), 1.80 (s, 3H), 1.32 (s, 9H). MS (ESI): m/e 389 (M+H).

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