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1. Scaffold-based [Fe]-hydrogenase model: H ₂ activation initiates Fe(0)-hydride extrusion and non-biomimetic hydride transfer

   https://doi.org/10.1039/D0SC03154B  

   Kerns, Spencer A.; Seo, Junhyeok; Lynch, Vincent M.; Shearer, Jason; Goralski, Sean T.; Sullivan, Eileen R.; Rose, Michael J. (October 2021, Chemical Science)

   We report the synthesis and reactivity of a model of [Fe]-hydrogenase derived from an anthracene-based scaffold that includes the endogenous, organometallic acyl(methylene) donor. In comparison to other non-scaffolded acyl-containing complexes, the complex described herein retains molecularly well-defined chemistry upon addition of multiple equivalents of exogenous base. Clean deprotonation of the acyl(methylene) C–H bond with a phenolate base results in the formation of a dimeric motif that contains a new Fe–C(methine) bond resulting from coordination of the deprotonated methylene unit to an adjacent iron center. This effective second carbanion in the ligand framework was demonstrated to drive heterolytic H 2 activation across the Fe( ii ) center. However, this process results in reductive elimination and liberation of the ligand to extrude a lower-valent Fe–carbonyl complex. Through a series of isotopic labelling experiments, structural characterization (XRD, XAS), and spectroscopic characterization (IR, NMR, EXAFS), a mechanistic pathway is presented for H 2 /hydride-induced loss of the organometallic acyl unit ( i.e. pyCH 2 –CO → pyCH 3 +CO). The known reduced hydride species [HFe(CO) 4 ] − and [HFe 3 (CO) 11 ] − have been observed as products by 1 H/ 2 H NMR and IR spectroscopies, as well as independent syntheses of PNP[HFe(CO) 4 ]. The former species ( i.e. [HFe(CO) 4 ] − ) is deduced to be the actual hydride transfer agent in the hydride transfer reaction (nominally catalyzed by the title compound) to a biomimetic substrate ([ Tol Im](BAr F ) = fluorinated imidazolium as hydride acceptor). This work provides mechanistic insight into the reasons for lack of functional biomimetic behavior (hydride transfer) in acyl(methylene)pyridine based mimics of [Fe]-hydrogenase. 

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2. Biomimetic Metal-Free Hydride Donor Catalysts for CO ₂ Reduction

   https://doi.org/10.1021/acs.accounts.1c00708  

   Ilic, Stefan; Gesiorski, Jonathan L.; Weerasooriya, Ravindra B.; Glusac, Ksenija D. (March 2022, Accounts of Chemical Research)
3. Hydride assisted synthesis of the high temperature thermoelectric phase: Yb ₁₄ MgSb ₁₁

   https://doi.org/10.1063/1.5117291  

   Justl, Andrew P.; Cerretti, Giacomo; Bux, Sabah K.; Kauzlarich, Susan M. (October 2019, Journal of Applied Physics)
4. Ternary antimonide NaCd ₄ Sb ₃ : hydride synthesis, crystal structure and transport properties

   https://doi.org/10.1002/zaac.202200095  

   Courteau, Brittany; Gvozdetskyi, Volodymyr; Lee, Shannon; Cox, Tori; Zaikina, Julia V. (May 2022, Zeitschrift für anorganische und allgemeine Chemie)

   Abstract A new compound NaCd₄Sb₃(Rm,a=4.7013(1) Å,c=35.325(1), Å, Z=3,T=100 K) featuring the RbCd₄As₃structure type has been discovered in the Na−Cd−Sb system, in addition to the previously reported NaCdSb phase. NaCd₄Sb₃and NaCdSb were herein synthesized using sodium hydride as the source of sodium. The hydride method allows for targeted sample composition, improved precursor mixing, and an overall quicker synthesis time when compared to traditional methods using Na metal as a precursor. The NaCd₄Sb₃structure was determined from single‐crystal X‐ray diffraction and contained the splitting of a Cd site not seen in previous isostructural phases. NaCd₄Sb₃decomposes into NaCdSb plus melt at 766 K, as determined viain‐situhigh‐temperature PXRD. The electronic structure calculations predict the NaCd₄Sb₃phase to be semi‐metallic, which compliments the measured thermoelectric property data, indicative of ap‐type semi‐metallic material. The crystal structure, elemental analysis, thermal properties, and electronic structure are herein discussed in further detail. 

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5. The spectroscopy of hydride in single crystals of SrTiO ₃ perovskite

   https://doi.org/10.1039/d4cp02852j  

   Palfey, William R; Hwang, Son-Jong; Goddard, William A; Rossman, George R (October 2024, Physical Chemistry Chemical Physics)

   Assisted by predictions from density functional theory, we used infrared spectroscopy to observe hydride ions introduced into SrTiO3 crystals. 

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