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Updated: Aug 15, 2025

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Phosphido-borane-supported stannates
Keith Izod1, Atheer M Madlool1, Alex Craig1
1Main Group Chemistry Laboratories, School of Chemistry, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK. keith.izod@ncl.ac.uk.
Abstract:
The reactions between SnCl2 and three equivalents of the alkali metal phosphido-borane complexes [R2P(BH3)]M yield the corresponding tris(phosphido-borane)stannate complexes [LM{R2P(BH3)}3Sn] [R2 = iPr2, LM = (THF)3Li (2Li), (Et2O)Na (2Na), (Et2O)K (2K); R2 = Ph2, LM = (THF)Li (3Li), (THF)(Et2O)Na (3Na), (THF)(Et2O)K (3K); R2 = iPrPh, LM = (THF)4Li (4Li)]. In each case X-ray crystallography reveals an anion consisting of a trigonal pyramidal tin centre coordinated by the P atoms of the phosphido-borane ligands. These tris(phosphido-borane)stannate anions coordinate to the alkali metal cations via their BH3 hydrogen atoms in a variety of modes to give monomers, dimers, and polymers, depending on the alkali metal and the substituents at the phosphorus centres. In contrast, reactions between SnCl2 and three equivalents of [tBu2P(BH3)]M (M = Li, Na) gave the known hydride [M{tBu2P(BH3)}2SnH], according to multinuclear NMR spectroscopy.
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