Table 3: Optimization of the conditions of 1,3-dipolar cycloaddition reaction of oxime 2a (1 mmol) with the propargyloxycoumarin 12a (1.1 mmol).

Entry	Reactants (mmol)	Solvent	T (°C)	Products (Yield %)
1	NCS (1.4), Et3N (1)	DMF	25	13a (28), 5a (25), 2a (45)
2	PIDA (1.1)	MeOH	25	13a (37), 5a (21), 1a (12)
3	PIDA (1.1), TFA (0.2)	MeOH	25	13a (64), 5a (16), 1a (9)
4	PIDA (1.1), TFA (0.2)	MeOH	0	13a (32), 5a (45)
5	PIDA (1.1), TFA (0.2)	MeOH	60	13a (19), 5a (23), 1a (42)
6	PIDA (1.1), TFA (0.2)	MeOH/H2O	25	13a (56), 5a (19), 1a (15)
7	PIDA (1.1), TFA (0.2)	DCM	25	13a (34), 5a (48), 1a (12)
8	PIDA (1.1), TFA (0.2)	THF	25	13a (25), 5a (52), 1a (19)
9	PIDA (1.1), TFA (0.6)	MeOH	25	13a (18), 5a (27), 1a (48)
10	PIDA (2), TFA (0.6)	MeOH	25	13a (14), 5a (31), 1a (37)
11	PIFA (1)	MeOH	25	13a (45), 5a (39), 1a (15)