Substituted 4-(1H-1,2,3-triazol-1-yl)-tetrafluorobenzoates: Selective synthesis and structure

Article abstract of DOI:10.1016/j.jfluchem.2016.05.005

Regioselective, simple and fast synthesis of a series of [2 + 3]-cycloaddition products, 2-11, 4-(4-RC₂HN₃)C₆F₄CO₂Et (2: R = Ph; 3: R = CMe₂OH; 4: R = CH₂OH; 5: R = CO₂Et; 6: R = n-C₅H₁₁; 7: R = CH₂O-o-C₆H₄CHO; 8: R = CH₂O-p-C₆H₄NHBoc; 9: R = CH₂O-p-C₆H₄CH₂OH; 10: R = CH₂O₂CC₆F₅; 11: R = p-C₆H₄Bu-t), in reaction between ethyl 4-azido-2,3,5,6-tetrafluorobenzoate, 1, and a number of substituted alkynes was elaborated under conditions of copper-catalyzed click chemistry reaction. The optimized conditions include application of CuBr and Et₃N in dichloromethane. The structure of compounds 2-11 was investigated in solution by 1D and 2D NMR and IR spectroscopy. The molecular structure of 2 in solid state was established by X-ray analysis.