22096-22-6Relevant articles and documents
Reversible Hydrogen Uptake/Release over a Sodium Phenoxide–Cyclohexanolate Pair
Yu, Yang,He, Teng,Wu, Anan,Pei, Qijun,Karkamkar, Abhijeet,Autrey, Tom,Chen, Ping
, p. 3102 - 3107 (2019/01/04)
Hydrogen uptake and release in arene–cycloalkane pairs provide an attractive opportunity for on-board and off-board hydrogen storage. However, the efficiency of arene–cycloalkane pairs currently is limited by unfavorable thermodynamics for hydrogen release. It is shown here that the thermodynamics can be optimized by replacement of H in the -OH group of cyclohexanol and phenol with alkali or alkaline earth metals. The enthalpy change upon dehydrogenation decreases substantially, which correlates with the delocalization of the oxygen electron to the benzene ring in phenoxides. Theoretical calculations reveal that replacement of H with a metal leads to a reduction of the HOMO–LUMO energy gap and elongation of the C?H bond in the α site in cyclohexanolate, which indicates that the cyclohexanol is activated upon metal substitution. The experimental results demonstrate that sodium phenoxide–cyclohexanolate, an air- and water-stable pair, can desorb hydrogen at ca. 413 K and 373 K in the solid form and in an aqueous solution, respectively. Hydrogenation, on the other hand, is accomplished at temperatures as low as 303 K.
Spiro Compounds As NPY Y5 Receptor Antagonists
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Page/Page column 50, (2009/08/18)
The present invention relates to novel compounds of formula (I), or a pharmaceutically acceptable salt thereof, wherein R is an aryl or heteroaryl, which may be substituted by one or more: halogen, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 haloalkyl, C1-C4 haloalkoxy, cyano;Z1 is H, C1-C4 alkyl or F;Z is CH2, CH(C1-C4 alkyl), C(C1-C4 alkyl)2 or a bond;A is a 6-10 membered aryl or heteroaryl, which may be substituted by one or more: halogen, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 haloalkyl, C1-C4 haloalkoxy, cyano; or —C(═O)—X; or —O(CH2)0-1R1;B is hydrogen or is a 5-6 membered heteroaryl, or a 4-6 membered heterocycle, or phenyl, which may be substituted by one or more: halogen, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 haloalkyl, C1-C4 haloalkoxy, hydroxyl, cyano; A and B being linked via any atom;R1 is —(C1-C4)alkyl(C1-C4)alkoxy; or C3-C8 cycloalkyl; or R1 is an aryl or heteroaryl, which may be substituted by one or more: halogen, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 haloalkyl, C1-C4 haloalkoxy, cyano; or R1 is a 4-6 membered heterocycle, which may be substituted by one or more: halogen, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 haloalkyl, C1-C4 haloalkoxy, cyano;X is OR2 or NR3R4;R2 is C1-C4 alkyl;R3 is hydrogen or together with R4 and the nitrogen form a 5-6 saturated membered ring;R4 is C3-C8 cycloalkyl; processes for their preparation, intermediates used in these processes, pharmaceutical compositions containing them and their use in therapy, as NPY Y5 receptor antagonists and as agents for the treatment and/or prophylaxis of eating disorders such as a binge eating disorder.
