110296-98-5Relevant academic research and scientific papers
Crystal structure of the uranium oxo borohydride complex U 2(μ-O)(BH4)6(dme)2 (dme = 1,2-dimethoxyethane) and reformulation of U2(μ-H) 2(BH4)6(dme)2
Daly, Scott R.,Ephritikhine, Michel,Girolami, Gregory S.
, p. 41 - 44 (2012)
The reaction of uranium tetrachloride, UCl4, with sodium N,N-dimethylaminodiboranate, Na(H3BNMe2BH3), in refluxing 1,2-dimethoxyethane (dme) yields small amounts of a new complex, which we formulate as (μ-oxo)hexakis(tetrahydroborato)bis(1,2- dimethoxyethane)diuranium(IV), toluene solvate, U2(μ-O)(BH 4)6(dme)2·C7H8, 1. Most likely, the formation of BH4- groups from H 3BNMe2BH3- occurs with the elimination of [Me2NBH2]2, and the formation of the oxo group involves adventitious hydrolysis. Each uranium center in 1 adopts a fac octahedral geometry (counting the BH4- groups as occupying one coordination site); the bridging oxygen atom and the two coordinated oxygen atoms of the dme ligand occupy positions trans to the three BH4- groups. The hydrogen atom positions were located in the electron density difference maps and reveal that all three BH 4- groups are bound in a κ3H fashion. The U...B distances to the two BH4- groups that are cis to the bridging oxygen atom are 2.574(6) and 2.584(6) , whereas the U...B distance of 2.635(7) to the BH4- group that is trans to the bridging oxygen is distinctly longer. Thus, the bridging oxygen atom exerts a noticeable trans influence. The crystallographic and 1H NMR data strongly suggest that the previously reported uranium hydride complex U 2(μ-H)2(BH4)6(dme)2 should be reformulated as this oxo complex U2(μ-O)(BH 4)6(dme)2.
