Synthesis and crystal structure of hexakis(ammonia–cyanoborane)- sodium iodide

Abstract

The preparation of the crystalline complex [Na{NH₃·BH₂(CN)}₆]I from NMe₃·BH₂I and NaCN in liquid NH₃ is described. Structural details have been obtained by single-crystal X-ray analysis of therhombohedral crystals which belong to space group R, with a=b=c= 8.506(4)Å, α=β=γ= 82.54(4)°, and Z= 1. The structure has been solved by the heavy-atom method from 1 293 unique reflections measured by diffractometer and refined by full-matrix least-squares calculations to R 0.063. The NH₃·BH₂(CN) units are arranged in a regular octahedral manner about both the Na⁺ and I^– ions with Na⁺⋯ N(cyano) 2.487(4)Å and Na⁺⋯ N–C 134.2(4)°; evidence for a linear correlation between such distances and angles in related complexes is presented. The B–N, B–C, and CN distances are 1.581(8), 1.579(8), and 1.152(7)Å, respectively.