A Facile One-Pot Solvent-Free Synthesis of 1,2-Dihydro-1-arylnaphtho[1,2-e][1,3]oxazine-3-ones Catalyzed by Wet Cyanuric Chloride

Table 1

Optimization of the reaction conditions in synthesis of 1,2-dihydro-1-arylnaphtho[1,2-e][1,3]oxazine-3-one^a.

Entry	TCT (moL%)	Reaction conditions	Time (min)	Yield (%)
1	10	EtOH/reflux	120	0
2	10	H2O/reflux	120	0
3	10	CH3CN/reflux	120	0
4	5	Solvent free/120°C	60	54
5	5	Solvent free/150°C	30	81
6	10	Solvent free/120°C	60	86
7	10	Solvent free/150°C	12	87
8	15	Solvent free/150°C	12	85

^a Reaction condition: β-naphthol (1 mmol), benzaldehyde (1 mmol), urea (1 mmol), TCT (10 mol%, 0.1 mmol) and, water (1-2 drops) in solvent-free condition at 150°C.