. 2018 Dec 18;3(12):17617–17628. doi: 10.1021/acsomega.8b02147

Table 3. Optimization Studies^a.

entry	base (equiv)	time (h)	solvent	% yield^b
1	KOAc (1.0)	19	CH₃CN	20
2	DBU (1.0)	1	CH₃CN	44
3	K₂CO₃ (1.0)	15	CH₃CN	71
4	Cs₂CO₃ (1.0)	15	CH₃CN	57
5	NaOH (1.0)	4	CH₃CN	50
6	KO^tBu (1.0)	4	CH₃CN	52
7	K₂CO₃ (1.0)	17	THF	45
8	K₂CO₃ (1.0)	18	CHCl₃	35
9	K₂CO₃ (1.0)	26	toluene	30
10	K₂CO₃ (0.5)	23	CH₃CN	47
11	K₂CO₃ (2.0)	12	CH₃CN	55
12	K₂CO₃ (1.0) (LiCl)^c	15	CH₃CN	44
13	K₂CO₃(1.0) (H₂O)^d	8	CH₃CN	76^e
14	K₂CO₃ (1.0)	15 min	CH₃CN	43^f

Reaction scale: 1a (0.23 mmol, 1.0 equiv), 5a (0.23 mmol, 1.0 equiv), and solvent (3 mL) at RT until complete consumption of at least one of the starting materials.

After column chromatography.

LiCl (0.23 mmol, 1.0 equiv).

CH₃CN/H₂O (97:3 v/v).

59% yield at 60 °C for 6 h.

Under microwave at 40 °C.

Table 3. Optimization Studiesa.

Table 3. Optimization Studies^a.