Hydrothermal synthesis method of 5-(4'-methylbiphenyl-2-yl)-1H-tetrazole

A clean and safe synthesis method of 5-(4'-methylbiphenyl-2-yl)-1H-tetrazole was found: under hydrothermal conditions, 1.2 equiv. of 4'-methylbiphenyl-2-carbonitrile react with 1 equiv. of sodium azide in a mixed solvent of propane-1,2-diol/H2O, with 1.5 equiv. of ammonium chloride and 0.2 equiv. of ammonium fluoride as catalyst. After simple post-processing, the yield can be improved to 95%, and the purity of the product is 99% without further recrystallization.