Fluorinated 1,2,3-Triazolines

Synthesis of 3,4-dihydro-1H-1,3,4-benzotriazepine-2,5-diones

“…These compounds represent the only authentic group of 3,4-dihydro-lH-l,3,4-benzotriazepinediones in the literature (vide infra). It is interesting to note that compounds 3 and 7 are selectively alkylated in the 4 and 3 positions, respectively, with no apparent competitive alkylation at position 1, since N-phenylamides are N-alkylated under these conditions.10 This selectivity is apparently another demonstration of the a effect.11 Langis and Charest12 report two methods for the preparation of 3,4-dihydro-lif-l,3,4-benzotriazepine-2,5-dione (11) and derivatives of 11. Their methods for 11 involve the cyclization of l-(2-aminobenzoyl)semicarbazide in decalin at reflux and treatment of 2-aminobenzoylhydrazine (10) with urea in decalin at reflux.…”

Fluorinated Triazoles and Tetrazoles

“…Thus, in 1966 Carpenter et al carried out the cycloaddition of benzyl azide to perfl uoroalkyl substituted acetylene derivatives leading to the formation of trifl uoromethyl-1,2,3-triazolines and 1,2,3-triazoles [ 39 ]. In this paper a synthesis of l-benzyl-4,5-bistrifl uoromethyl-l,2,3-triazole 31 from hexafl uoro-2-butyne was described.…”

“…Сarpenter et al synthesized 1-benzyl-5-trifl uoromethyltetrazole 100 by replacing the fl uorine atom in N-benzyltrifl uoroacetimidoyl fl uoride by an azide group followed by electrocyclic cyclization of the intermediate imidoyl azide (azidoazomethine). The yield of purifi ed product 100 is unknown [ 39 ]. 1,3-Dipolar cycloaddition of perfl uoroalkylethyl azides to isocyanates afforded 1-perfl uoroalkyl-4-( n -Bu, phenyl or mesitylsulfonyl) tetrazol-5-ones 101 in good yields [ 96 ].…”

An Overview of 4‐ and 5‐Halo‐1,2,3‐triazoles from Cycloaddition Reactions

“…To our knowledge the first methodology that reports the synthesis of 4‐fluoro‐1,5‐disubstituted‐1,2,3‐triazole was described in 1966 by Moore et al [80] . The condensation of benzyl azide with perfluoropropene at 150 °C gives the 1,2,3‐triazoline, which in the presence of tetrakis (dimethylamino)ethylene (TDAE), is converted to the 4‐fluoro‐1,2,3‐triazole 83 (Scheme 51).…”