反应详情

(±)-(E)-3-{1′-Tert-butoxycarbonyl-3,4-dihydro-4-oxo-spiro[2H-(1,3)-benzoxazine-2,3′-piperidin]-6-yl}-acrylic acid methyl ester (1.90 g, 4.72 mmol) in DCM (33 ml) was treated with 4 M HCl in dioxane (5.90 ml) as described for Intermediate 4, Step C, giving (±)-(E)-3-{3,4-dihydro-4-oxo-spiro[2H-(1,3)-benzoxazine-2,3′-piperidin]-6-yl}-acrylic acid methyl ester (1.35 g, hydrochloride salt) as a light brown solid.