One‐Pot Synthesis of 1,3,5‐Triarylpyrazoles

A series of novel 1,3,5-triarylpyrazoles were synthesized from flavanones, arylhydrazines, and trimethyl phosphate in an one-pot procedure. Facile reaction process, easy after-reaction workshop, and good yields are the distinct characteristics of the developed protocol. The target compounds were characterized by element analysis, infrared ray (IR), 1H NMR spectra, and electrospray ionization-mass spectrometry. The structure of representative compound (C23H20N2O3, Mr = 372.42) was further confirmed by X-ray diffraction. It crystallizes in monoclinic, space group P 21/c, a = 8.9720(5), b = 24.5523(13), c = 8.9687(6) A, α = 90.0000, β = 102.6417(17), γ = 90.0000°, V = 1927.76(20) A3, Z = 4, μ(MoKα) = 0.086, F(000) = 784, Dc = 1.283 g/cm3, the final R = 0.0349 and wR = 0.0844 for 1668 observed reflections (I > 2σ(I))