Efficient syntheses of ω-chloro-, ω-imido- and ω-aminoalkyl-1,2,4-triazoles from N-acyl-formamidinium salts or N-acylformamides and hydrazines

Article abstract of DOI:10.1002/ardp.19923250813

ω-Halo and ω-amidoalkylcyanides 1 are transformed to ω-functionalized N-acylformamidinium salts 4 or formamide 6a by HCl catalyzed addition of chloromethylene iminium salts, derived from formamides 2 and POCl₃. Advantageously, β-halo-propionyl-