Cu-MOF catalyzed synthesis of benzoxanthenone derivatives (4a–j)^a.

Entry	Aldehyde	Product	Product structure	Time (min)	Yieldb (%)	Mpc (°C)
1		4a		25	90	150–151c
2		4b		40	85	174–176c
3		4c		60	80	205–206c
4		4d		60	85	202–204c
5		4e		50	80	193–194c
6		4f		20	84	184–186c
7		4g		60	88	205–206c
8		4h		50	92	180–182
9		4i		60	90	185–187
10		4j		60	90	170–172

^aConditions: 1 (1 mmol), 2 (1 mmol), 3 (1 mmol), Cu-MOF (0.05 g), stirring at 60–70 °C.

^bProduct yield.

^cMelting points of known cpds match with literature values.^35,36