The Recycling of Spent Ammonia Borane with HBr/AlBr3 and Other HX/AlX3‐Based Schemes. Issue 11 (16th October 2018)

• Record Type: Journal Article
• Authors: Reller, Christian; Mertens, Florian
• Is Part Of: ChemPlusChem. Volume 83:Issue 11(2018)
• Page Start: 1013
• Page End: 1020
• Publication Date: 2018-10-16
• Subjects: ammonia borane -- BNH waste -- boron compounds -- hydrodehalogenation -- nickel boride; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.201800347
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: Although the development and application of a BNHx ‐waste recycling process is one of the major prerequisites for the use of ammonia borane as hydrogen source material, most research groups in the field have focused on AB hydrogen release and only few groups have worked on the development of energetically viable recycling schemes. In our work we target the development of a closed recycling process containing three desired steps: superacid break‐up of the BNHx ‐waste, catalytic hydrodehalogenation of the generated boron halide, and base‐exchange between Et3 NBH3 and ammonia. Catalytic hydrodehalogenation provides a convenient means to generate B−H bonds using molecular hydrogen, avoiding potentially energetically expensive reduction reagents. Abstract : Completing the cycle : Energy‐efficient recycling of spent ammonia borane is a prerequisite for the large‐scale application of this class of materials as a hydrogen source. A proposed process provides new ways to produce valuable borane nitrogen compounds suitable for highly specific reductions in organic synthesis. Elements of the presented hydrodehalogenation may also be applicable to the treatment of other halogen‐containing waste materials.