Charge-Enhanced Reactivity of Esters by a Cationic Substituent
Masaaki Sakuma1, Ryosuke Haraguchi1
1Department of Applied Chemistry, Graduate School of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan.
Abstract:
In this study, the high electrophilicity of carbonyl carbons attached to cationic heterocycles was observed. Triazolium-substituted esters underwent catalyst-free amidation with aliphatic amines at -50 °C and reduction with NaBH4 at -100 °C. The origin and generality of the high reactivity of these esters were systematically investigated. The findings of this work were utilized for the postmodification of N-heterocyclic carbenes, which are utilized as promising ligands in a wide range of transition-metal-catalyzed reactions.
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