Microwave-Assisted Iodination: Synthesis of Heavily Iodinated 10-Vertex and 12-Vertex Boron Clusters

Abstract

Microwave-assisted syntheses of heavily iodinated 10-vertex and 12-vertex closo boron clusters are reported. Salts of closo-B₁₀I₁₀²⁻, 1-carba-closo-CHB₉H₄I₅⁻, 1-carba-closo-CB₁₁H₆I₆⁻, 1-carba-closo-CHB₁₁I₁₁⁻, and B₁₂I₁₂²⁻ were prepared in yields of 80% or better. All molecules were characterized by NMR and IR spectroscopy and mass spectrometry. The crystal structure of [Et₄N][CHB₉H₄I₅] was determined by single crystal X-ray diffraction. This salt crystallizes in the monoclinic P2(1)/c space group, a = 9.74427(12) Å, b = 20.7512(2) Å, c = 13.06589(17) Å, b = 101.2176(12)°, V = 2591.52(6) ų, Z = 4, and r_c = 2.262 g/cm³.

Keywords:

• carboranes, boron clusters, iodination, microwave synthesis

Acknowledgments

The authors thank Greg Dwulet, Clint Vorauer, and Hannah Midget for assistance with carborane syntheses.

Funding

This work was supported by the M. J. Murdock Charitable Trust, funds from Whitman College and the National Science Foundation (CHE-0922775).