Peanut shell as a green biomolecule support for anchoring Cu2O: a biocatalyst for green synthesis of 1,2,3-triazoles under ultrasonic irradiation

Table 1 Screening of the reaction conditions

Entry	Solvent/T (°C)	Base	Cat. (mol%)	Method	Yield (%)^a
1	Toluene/50	K₂CO₃	1	Ultrasound	Trace
2	MeCN/50	K₂CO₃	1	Ultrasound	65
3	MeOH/50	K₂CO₃	1	Ultrasound	77
4	EtOH/50	K₂CO₃	1	Ultrasound	72
5	H₂O/50	K₂CO₃	1	Ultrasound	73
6	EtOH-H₂O/50	K₂CO₃	1	Ultrasound	91
7	MeOH-H₂O/50	K₂CO₃	1	Ultrasound	74
8	EtOH-H₂O/50	Cs₂CO₃	1	Ultrasound	53
9	EtOH-H₂O/50	KOt-Bu	1	Ultrasound	49
10	EtOH-H₂O/50	NaOH	1	Ultrasound	69
11	EtOH-H₂O/50	KOH	1	Ultrasound	71
12	EtOH-H₂O/70	K₂CO₃	1	Ultrasound	86
13	EtOH-H₂O/40	K₂CO₃	1	Ultrasound	71
14	EtOH-H₂O/room temperature	K₂CO₃	1	Ultrasound	57
15	EtOH-H₂O/50	K₂CO₃	0.5	Ultrasound	65
16	EtOH-H₂O/50	K₂CO₃	2	Ultrasound	92
17	EtOH-H₂O/50	K₂CO₃	–	Ultrasound	Trace
18	EtOH-H₂O/50	K₂CO₃	1	High-speed stirring	56
19	MeOH-H₂O/50	K₂CO₃	1	High-speed stirring	44
20	H₂O/50	K₂CO₃	1	High-speed stirring	48
21^b	EtOH-H₂O/50	K₂CO₃	40 mg	Ultrasound	Trace
22^c	EtOH-H₂O/50	K₂CO₃	1	Ultrasound	78

4-Nitro benzyl bromide (1 mmol), phenylacetylene (1.2 mmol), K₂CO₃ (2 mmol), NaN₃ (1.2 mmol), 45 min
^aIsolated yield
^bCat. = PS (40 mg)
^cCat. = Cu₂O (1 mol%)

ISSN: 2661-801X