Copper(I) Acetate: A Structurally Simple but Highly Efficient Dinuclear Catalyst
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Experimental Section
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Typical Procedure; Preparation of 1-Benzyl-4-phenyl-
1H-[1,2,3]triazole (3a) by [(CH3CO2Cu)2]n (Cat-1)-
Catalyzed CuAAC under Solvent-Free Conditions
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A solution of [(CH3CO2Cu)2]n in Et2O (1 mL) {it was made
from [(CH3CO2Cu)2]n (12.5 mg) in Et2O (10 mL)} was
evaporated under N2 to yield a powder of [(CH3CO2Cu)2]n
(1.25 mg, 0.01 mmol, 0.5 mol%, MW was calculated based
on CH3CO2Cu). To this powder was added a mixture of phe-
nylethyne (1a, 204 mg, 2 mmol) and benzyl azide (2a,
280 mg, 2.1 mmol) at room temperature. The resultant mix-
ture was stirred continuously until the reaction system had
solidified completely (ca. 3 min). After the crude product
had been diluted with CH2Cl2 (2 mL), it was purified by a
short chromatography (silica gel, EtOAc:PE=1:3) to give
3a as an off-white solid; yield: 464 mg (99%).
Typical Procedure; Preparation of 1-Benzyl-4-phenyl-
1H-[1,2,3]triazole (3a) by [(CH3CO2Cu)2]n (Cat-1)-
Catalyzed CuAAC in Cyclohexane
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A solution of [(CH3CO2Cu)2]n in Et2O (1 mL) {it was made
from [(CH3CO2Cu)2]n (25 mg) in Et2O (10 mL)} was evapo-
rated under N2 to yield a powder of [(CH3CO2Cu)2]n
(2.5 mg, 0.01 mmol, 1 mol%, MW was calculated based on
CH3CO2Cu). To this powder was added a solution of phe-
nylethyne (1a, 204 mg, 2 mmol) and benzyl azide (2a,
280 mg, 2.1 mmol) in cyclohexane (1 mL) at room tempera-
ture. The resultant mixture was stirred continuously until
phenylethyne was exhausted (ca. 8 min). After the crude
product had been diluted by CH2Cl2 (2 mL), it was purified
by a short chromatography (silica gel, EtOAc:PE=1:3) to
give 3a as an off-white solid; yield: 459 mg (98%).
A similar procedure was used in CuAAC for the prepara-
tion of triazole products 3b–q (see Scheme 4 and Scheme 5
in the text).
Supporting Information
The experimental details, characterization data, 1H NMR
and 13C NMR spectra for products 3a–q are available in the
Supporting Information.
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Acknowledgements
This work was supported by the NNSFC (20672066,
30600779) and CFKSTIP from Education Ministry of China
(706003).
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