Miscellaneous Routes for the Synthesis of 1,2,3-Triazoles

Although various research efforts have resulted in alternative cyclization strategies, even now alkynes are frequently employed for the formation of 

R2 = H, mesityl, Ph, o-tolyl, p-anisyl, Bu, 2-pyridyl, 26-92% yields COgEt, Cgp5, p-NOgPh, p-CFgPh, p-HOCHjPh 23 examples Ar = Ph, CgFg, p-BrPh, p-tolyl, 3,4,5-(MeO)3Ph, mesityl 

Not surprisingly, when is a phenyl group in the azide, the lowest yields (112c, 

120a (R = CHjOBn, 78%) 120b (R = CHjOBn, 85%) 120c (R = CHjOBn, 83%) 

R = Ph, 4-CIPh, 4-MeOPh R2= Ph, c-hexyl, H, Bu, COjMe, CHjOPh R = Bn, 1-adamantyl, alkyl 

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