Synthesis and characterization of click-decahydrodecaborate derivatives by the copper(I) catalyzed [3+2] azide-alkyne cycloaddition reaction

A facile and rapid access to a wide range of novel 1,2,3-triazoles bearing closo-decahydrodecaborate anion [B10H10](2-) has been developed through an efficient general synthetic approach. It is based on the nucleophilic cleavage of 2-tetrahydrofuranium decaborate with sodium azide to form the known [B10H9O(CH2)(4)N-3](2). This azide derivative obtained reacted with various linear alkynes (phenylacetylene, 5-chloro-1-pentyne, heptyne, octyne, N-Boc-propargylamine and diethyl acetylenedicarboxylate) by the copper(I) catalyzed [3 + 2] azide-alkyne cycloaddition reaction (CuAAC) to form click-decaborate derivatives. In absence of copper and with strained cycloalkynes, the reaction is a strain-promoted cyclo-alkyne-azide cycloaddition (SPAAC). All click-decaborate derivatives were obtained in pure form with high yields and characterized by B-11, H-1 and C-13 NMR, MS-ESI, and Atomic Absorption. (C) 2018 Elsevier B.V. All rights reserved.