Possessing high H(2) capacities and interesting dehydrogenation behavior, metal amidoborane ammoniates were prepared by reacting Ca(NH(2) )(2) , MgNH, and LiNH(2) with ammonia borane to form Ca(NH(2) BH(3) )(2) ⋅2 NH(3) , Mg(NH(2) BH(3) )(2) ⋅NH(3) , and Li(NH(2) BH(3) )(2) ⋅NH(3) (LiAB⋅NH(3) ). Insight into the mechanisms of amidoborane ammoniate formation and dehydrogenation was obtained by using isotopic labeling techniques. Selective (15) N and (2) H labeling showed that the formation of the ammoniate occurs via the transfer of one H(N) from ammonia borane to the [NH(2) ](-) unit in Ca(NH(2) )(2) giving rise to NH(3) and [NH(2) BH(3) ](-) . Supported by theoretical calculations, it is suggested that the improved dehydrogenation properties of metal amidoborane ammoniates compared to metal amidoboranes are a result of the participation of a strong dihydrogen bond between the NH(3) molecule and [NH(2) BH(3) ](-) . Our study elucidates the reaction pathway involved in the synthesis and dehydrogenation of Ca(NH(2) BH(3) )(2) ⋅2 NH(3) , and clarifies our understanding of the role of NH(3) , that is, it is not only involved in stabilizing the structure, but also in improving the dehydrogenation properties of metal amidoboranes.
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http://dx.doi.org/10.1002/cssc.201100523 | DOI Listing |
J Agric Food Chem
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Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China.
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College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, Zhejiang 314001, China. Electronic address:
Electro-reforming of organics such as alcohols into commodity chemicals and H powered by renewables is intriguing and prevailing with the remarkable renaissance of electrochemical technology. Integrating Pt/Pd with an auxiliary metal, metal oxide, and metal hydroxide are feasible strategies to design the desirable catalysts toward alcohols electro-oxidation reactions. These catalysts however have high affinity toward carbonyl intermediates that occupy and poison the active sites.
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Advanced Materials Research Group, Faculty of Engineering, University of Nottingham, Nottingham NG7 2RD, United Kingdom.
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College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.
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February 2025
Department of Biochemistry, School of Dentistry, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya, 464-8650, Japan. Electronic address:
The pink-colored Cypridina luciferase (CypLase∗) from Cypridina (Vargula) hilgendorfii contains an unknown chromophore (CypL∗), derived from Cypridina luciferin (CypL). When CypLase∗ was treated with NAD(P)H-FMN flavin reductase (FRase) and NADH, the luminescence intensity in the reaction mixture increased significantly after gentle tapping. This observation suggests that CypL∗ in CypLase is enzymatically converted to CypL by the reduced flavin (FMNH) through the FRase reaction, and the resulting complex of CypL and CypLase reacts with O to emit light.
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