Method for Assigning Structure of 1,2,3-Triazoles

Abstract

1,4-Disubstituted-1H-1,2,3-triazoles 1 can easily be distinguished from the isomeric 1,5-disubstituted-1H-1,2,3-triazoles 2 by simple one-dimensional (13)C NMR spectroscopy using gated decoupling. The C(5) signal of 1 appears at δ ∼120 ppm, while the C(4) signal of 2 appears at δ ∼133 ppm. Computational studies also predict the upfield shift of C(5) of 1 relative to C(4) in 2.

Ruthenium-Catalyzed Azide Alkyne Cycloaddition Reaction: Scope, Mechanism, and Applications

“…65,77 Creary et al sought to develop a simpler means of distinguishing between the 1,4-and 1,5-isomer of a 1,2,3-triazole using 13 C NMR. 78 isomers. 78 The heterocyclic ring of triazoles contains three nitrogen atoms that could potentially also be analyzed using NMR.…”

“…78 isomers. 78 The heterocyclic ring of triazoles contains three nitrogen atoms that could potentially also be analyzed using NMR. The low natural abundance and sensitivity of 15 …”

Synthesis of Isoxazole and 1,2,3-Triazole Isoindole Derivatives via Silver- and Copper-Catalyzed 1,3-Dipolar Cycloaddition Reaction

“…An additional proof concerning the regiochemistry of the copper-catalyzed [3+2] cycloaddition reaction is provided by the 13 C-NMR data. The chemicals shifts of the carbon atom 5-C at δ = 120.0 ppm and that of carbon 4-C at δ = 143.8 ppm are characteristic for 1,4-disubstituted-1H-1,2,3-triazoles [47][48][49][50][51]. The C atom 4-C of the hypothetical isomeric compound 7a should appear at around 133 ppm [51].…”

“…The chemicals shifts of the carbon atom 5-C at δ = 120.0 ppm and that of carbon 4-C at δ = 143.8 ppm are characteristic for 1,4-disubstituted-1H-1,2,3-triazoles [47][48][49][50][51]. The C atom 4-C of the hypothetical isomeric compound 7a should appear at around 133 ppm [51]. Formation of these regioisomeric 1,5-disubstituted-1H-1,2,3-triazoles has been reported to occur by Ru-catalyzed cycloaddition [52,53], but we are not aware of copper-catalyzed reactions leading to these isomers.…”

Multicomponent Click Synthesis of New 1,2,3-Triazole Derivatives of Pyrimidine Nucleobases: Promising Acidic Corrosion Inhibitors for Steel

“…Based on our previously reported methodology [29,51], the reaction between monopropargyl nucleobases 3-4, sodium azide, and several benzyl halides was carried out in the presence of a catalytic amount of Cu(OAc) 2 ·H 2 O in EtOH-H 2 O (2:1 v/v) at room temperature for 24 h to give the desired products 5-14 in good yields (Table 1). [29,51,52].…”