title: Understanding the Origins of Nucleophilic Hydride Reactivity of a Sodium Hydride-Iodide Composite.
abstract: Sodium hydride (NaH) has been commonly used as a Brønsted base in chemical syntheses, while it has rarely been employed to add hydride (H(-) ) to unsaturated electrophiles. We previously developed a procedure to activate NaH through the addition of a soluble iodide source and found that the new NaH-NaI composite can effect even stereoselective nucleophilic hydride reductions of nitriles, imines, and carbonyl compounds. In this work, we report that mixing NaH with NaI or LiI in tetrahydrofuran (THF) as a solvent provides a new inorganic composite, which consists of NaI interspersed with activated NaH, as revealed by powder X-ray diffraction, and both solid-state NMR and X-ray photoelectron spectroscopies. DFT calculations imply that this remarkably simple inorganic composite, which is comprised of NaH and NaI, gains nucleophilic hydridic character similar to covalent hydrides, resulting in unprecedented and unique hydride donor chemical reactivity.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
authors.forename: Zonghan
authors.initials: Z
authors.lastname: Hong
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
authors.forename: Derek Yiren
authors.initials: DY
authors.lastname: Ong
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.|Energy Research Institute@NTU, Nanyang Technological University, Research Techno Plaza, Singapore, 637553, Singapore.
authors.forename: Subas Kumar
authors.initials: SK
authors.lastname: Muduli
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
authors.forename: Pei Chui
authors.initials: PC
authors.lastname: Too
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
authors.forename: Guo Hao
authors.initials: GH
authors.lastname: Chan
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
authors.forename: Ya Lin
authors.initials: YL
authors.lastname: Tnay
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore. Shunsuke@ntu.edu.sg.
authors.forename: Shunsuke
authors.identifier: 0000-0003-2039-023X
authors.initials: S
authors.lastname: Chiba
authors.affiliation: RIKEN CLST-JEOL Collaboration Center, Yokohama, Kanagawa 230-0045 (Japan). yunishiy@jeol.co.jp.|JEOL RESONANCE Inc. Akishima, Tokyo, 196-8558, Japan. yunishiy@jeol.co.jp.
authors.forename: Yusuke
authors.identifier: 0000-0001-7136-1127
authors.initials: Y
authors.lastname: Nishiyama
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore. hirao@ntu.edu.sg.
authors.forename: Hajime
authors.identifier: 0000-0002-8239-3471
authors.initials: H
authors.lastname: Hirao
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore. hansen@ntu.edu.sg.|Solar Fuels Laboratory, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 637553, Singapore. hansen@ntu.edu.sg.|Singapore-Berkeley Research Initiative for Sustainable Energy (SinBeRISE), 1 Create Way, Singapore, 138602, Singapore. hansen@ntu.edu.sg.
authors.forename: Han Sen
authors.identifier: 0000-0001-6502-2313
authors.initials: HS
authors.lastname: Soo
keywords: NMR spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; density functional calculations; sodium hydride-iodide composite