An Enolate-Mediated Organocatalytic Azide-Ketone [3+2]-Cycloaddition Reaction: Regioselective High-Yielding Synthesis of Fully Decorated 1,2,3-Triazoles

An enolate‐mediated organocatalytic azide–ketone [3+2]‐cycloaddition (OrgAKC) reaction of a variety of enolizable arylacetones and deoxybenzoins with aryl azides was developed for the synthesis of fully decorated 1,4‐diaryl‐5‐methyl(alkyl)‐1,2,3‐triazoles in excellent yields with high regioselectivity at 25 °C for 0.5–6 h. This reaction has an excellent outcome with reference to reaction rate, yield, regioselectivity, operation simplicity, and availability of substrates and catalyst. This reaction has advantages over the previously known metal‐mediated reactions. Fully functionalized 1,2,3‐triazoles were synthesized by a metal‐free clicking through an enolate‐mediated organocatalytic azide–ketone [3+2]‐cycloaddition (OrgAKC) reaction. Very simple and readily available aryl azides and enolizable arylacetones/deoxybenzoins were employed in this organocatalytic transformation (see scheme; DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene).