Morpholine → 6-Methylspiro[2H-1,3-benzoxazine-2,4′-piperidin]-4(3H)-one

Participants

Reaction Steps

A mixture of 26 mg (0.083 mmol) of N-[4,8-dimethoxyquinoline-2-yl)carbonyl]-4-piperidone (prepared as described in Example 44), 12.5 mg (0.083 mmol) of 2-hydroxy-5-methylbenzamide, and 0.020 mL of morpholine in 2 mL of methanol is refluxed for 20 hr. The reaction mixture is diluted with ethyl acetate, and washed with water, brine, and dried over Na2SO4. After solvent removal by rotoevaporation, the crude product is purified by preparative TLC to give 20 mg (0.045 mmol, 54% yield) of 1′-[4,8-dimethoxyquinoline-2-yl)carbonyl]-6-methylspiro-[2H-1,3-benzoxazin-2,4′-piperidin]-4-(3H)-one (Compound 137): 1H NMR (DMSO-d6): δ 2.28 (s, 3H), 3.95 (s, 3H), 4.06 (s, 3H), 6.98 (d, 1H), 7.19 (s, 1H), 7.23 (d of d, 1H), 7.33 (d of d, 1H), 7.52 (d of d, 1H), 7.56 (d, 1H), 7.68 (d of d, 1H), and 8.77 ppm (s, 1H). MS m/z: 448.1 (M+H)+, 470.0 (M+Na)+.

Provenance & Evidence