Synthesis of 2-aryl-1,2-dihydronaphtho[1,2-f][1,4]oxazepin-3(4H)-ones. Part I

Abstract

Oxazepines, which were synthesized in literature by means a variety of methods, are of great importance in heterocyclic chemistry along with biology and pharmacology. In this work we tried to synthesize naphthoxazepines by using a number of Schiff bases, which were synthesized from 2-hydroxy-1-napthaldehyde and anilines. The obtained imines were reduced to amines, acylated with chloroacetyl chloride and cyclised to give naphthoxazepinones in an overall yield of 20-49%. The identifications of the isolated and purified compounds were determined by IR, UV, 1 H-NMR, 13 C-NMR, mass spectra and elemental analysis.

Mild and Rapid Method for the Generation of ortho-(Naphtho)quinone Methide Intermediates

“…R f = 0.70 (20% ethyl acetate in hexane). 1 H NMR (250 MHz, CDCl 3 ) δ: 8.22-8.11 (q, 1H, J = 8.7 Hz, 9.2 Hz), 7.80-7.67 (m, 2H), 7.55-7.49 (t, 1H, J = 7.9 Hz, 7.0 Hz), 7.40-7.37 (d, 1H, J = 7.3 Hz), 7.14-7.06 (t, 1H, J = 8 Hz), 5.16 (s, 2H), 1.06 (s, 9H), 0.28 (s, 6H); 13…”

“…129-131 °C. 1 H NMR (250 MHz, CDCl 3 ) δ: 10.07 (s, 2H), 7.26-7.35 (m, 5H), 7.18-7.16 (d, 2H, J = 6.6Hz), 7.11-7.05 (t, 2H, J = 7.6 Hz), 6.79-OH N S6 6.74 (t, 4H, J = 7.9 Hz, 5.6 Hz), 3.58 (s, 6H); 13 According to the general procedure, the nitrate ester 4a (200 mg, 0.7 mmol) and panisidine (95 mg, 0.77 mmol) were reacted with TBAF (0.7 mL, 0.7 mmol) in THF (8 mL) at -78 °C. Subsequent workup and flash column chromatography (5% ethyl acetate in hexane) yielded 5d as an off white solid which was recrystallized from hexane to afford 5d as off white microcrystals (50 mg, 30% yield).…”

“…R f = 0.47 (40% ethyl acetate in hexane). 1 H NMR (250 MHz, DMSO-d 6 ) δ: 9.51 (s, 1H), 7.05-6.97 (q, 2H, J = 7.4 Hz), 6.78-6.75 (d, 1H, J = 7.9 Hz), 6.70-6.64 (t, 1H, J = 7.4 Hz), 4.09-4.01 (q, 4H), 3.82-3.75 (t, 1H), 3.01-2.98 (d, 2H), 1.12-1.06 (m, 6H); 13…”

“…125-127 °C identical in all respects to an authentic sample. 13 General procedure for hetero Diels-Alder reaction of the nitrate ester (4a)…”

“…R f = 0.26 (10% ethyl acetate in hexane). 1 H NMR (250 MHz, CDCl ) δ: 7.38-7.35 (d, 1H, J = 7.4 Hz), 7.14-7.08 (t, 1H, J = 7.8 Hz), 6.96-6.90 (t, 1H, J = 7.2 Hz), 6.81-6.78 (d, 1H, J = 7.9 Hz), 3.65 (s, 2H), 2.55 (s, 4H), 1.77 (s, 4H) 1.03 (s, 9H), 0.23 (s, 6H); 13 GVAS23@250 C−13…”