The assignment of 11B and 1H resonances in the post-reaction mixture from the dry synthesis of Li(BH3NH2BH2NH2BH3)

Ewa K. Nawrocka,  Agnieszka Prus, Rafał Owarzany, Wiktor Koźmiński, Krzysztof Kazimierczuk, Karol J. Fijalkowski

We report a detailed 1H NMR and 11B NMR study of as synthesised Li(BH3NH2BH2NH2BH3) obtained in a novel dry-synthesis method. A combination of 1D and 2D single- and triple quantum techniques was used for the assignment of all observed signals. Minor side-products and reactants were detected in the product: NH3BH3, Li(NH2BH3), Li(BH4) and two yet unknown salts containing 7-membered chain anions: (BH3NH2BH2NH2BH2NH2BH3)– and (BH(NH2BH3)_3)-. We believe the assignment provided within this study might be helpful when analysing the mixtures containing numerous ammonia borane derivatives which often give overlapping signals which are hard to distinguish.

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