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Updated: May 10, 2026

Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
Published on: October 3, 2014
High yielding preparation of dicarba-closo-dodecaboranes using a silver(I) mediated dehydrogenative alkyne-insertion
Antonio Toppino1, Afaf R Genady, Mohamed E El-Zaria
1Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
Abstract:
The synthesis of 1,2-dicarba-closo-dodecaboranes (ortho-carboranes) is often low yielding which is a critical issue given the increasing use of boron clusters in material science and medicinal chemistry. To address this barrier, a series of Cu, Ag, and Au salts were screened to identify compounds that would enhance the yields of ortho-caboranes produced when treating alkynes with B10H12(CH3CN)2. Using a variety of functionalized ligands including mono- and polyfunctional internal and terminal alkynes, significant increases in yield were observed when AgNO3 was used in catalytic amounts. AgNO3 appears to prevent unwanted reduction/hydroboration of the alkyne prior to carborane formation, and the process is compatible with aryl, halo, hydroxy, nitrile, carbamate, and carbonyl functionalized alkynes.
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