cas 7784-21-6, Aluminium hydride | Articles data

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Catalytic synthesis of aluminum hydride in the presence of palladium black
The catalytic properties of a palladium catalyst in the formation of aluminum hydride are studied. The formation of stoichiometric aluminum hydride is determined by XRD, DTA, and spectrophotometry. Findings are rationalized in terms of the electron-chemical catalytic scheme.
Normatov
p. 558 - 560
(2004)
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Powerful Surface Chemistry Approach for the Grafting of Alkyl Multilayers on Aluminum Nanoparticles
The synthesis of aluminum nanoparticles (Alnp) has raised promising perspectives these past few years for applications in energetic materials. However, because of their high reactivity, it is crucial to functionalize them before their use. In this work, we propose an original and simple chemical approach to graft spontaneously alkyl layers derived from alkyl halides at the surface of Alnp, by relying on the highly reductive character of these nanoparticles, when they are in the unoxidized form. Alnp were prepared in a glovebox and reacted with alkyl halides (RI and RBr) to give modified Alnp-R, as shown by infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction, thermogravimetric analysis (TGA), and microscopy. The coating is made of alkyl multilayers, which were found to be strongly anchored at the Alnp surface, as it resisted 2 h of rinsing in toluene. An electrocatalytic electron transfer promoted by Alnp is proposed to describe the mechanism of this grafting reaction.
Fogliazza, Morgan,Sicard, Lorette,Decorse, Philippe,Chevillot-Biraud, Alexandre,Mangeney, Claire,Pinson, Jean
p. 6092 - 6098
(2015)
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Surface changes on AlH3 during the hydrogen desorption
Surface change of α -AlH3 during the hydrogen desorption was investigated by means of in situ x-ray photoelectron spectroscopy combined with thermal desorption spectroscopy. The surface of AlH3 covered by an oxide layer significantly changes upon hydrogen desorption and the hydrogen desorption rate increases remarkably. In this study, the role of the surface oxide layer on AlH3 in view of the hydrogen desorption kinetics was investigated. AlH3 only decomposes into Al and H2 at the free surface and not in the bulk. Therefore, a closed surface oxide layer prevents the thermodynamically unstable AlH3 from decomposition.
Kato, Shunsuke,Bielmann, Michael,Ikeda, Kazutaka,Orimo, Shin-Ichi,Borgschulte, Andreas,Zuettel, Andreas
(2010)
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METHYLIDYNE TRICOBALT NONACARBONYL CLUSTERS; OPTICALLY ACTIVE SILICON AND GERMANIUM DERIVATIVES, AND SUBSTITUTIONS AT SILICON
The preparation and alcoholysis of chiral chlorosilanes containing the noncarbonyltricobaltcarbon cluster, RR'Si(Cl)CCo3(CO)9, is described.The alkoxy derivatives react with i-Bu2AlH or BF3*Et2O to give the corresponding silicon hydride or fluoride.Reacti
Combes, Christian E. J.,Corriu, Robert J. P.,Henner, Bernard J. L.
p. 257 - 270
(1981)
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Aluminium hydride: A reversible material for hydrogen storage
Aluminium hydride has been synthesized electrochemically, providing a synthetic route which closes a reversible cycle for regeneration of the material and bypasses expensive thermodynamic costs which have precluded AlH3 from being considered as
Zidan, Ragaiy,Garcia-Diaz, Brenda L.,Fewox, Christopher S.,Stowe, Ashley C.,Gray, Joshua R.,Harter, Andrew G.
p. 3717 - 3719
(2009)
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A Universally Applicable Methodology for the Gram-Scale Synthesis of Primary, Secondary, and Tertiary Phosphines
Although organophosphine syntheses have been known for the better part of a century, the synthesis of phosphines still represents an arduous task for even veteran synthetic chemists. Phosphines as a class of compounds vary greatly in their air sensitivity, and the misconception that it is trivial or even easy for a novice chemist to attempt a seemingly straightforward synthesis can have disastrous results. To simplify the task, we have previously developed a methodology that uses benchtop intermediates to access a wide variety of phosphine oxides (an immediate precursor to phosphines). This synthetic approach saves the air-free handling until the last step (reduction to and isolation of the phosphine). Presented herein is a complete general procedure for the facile reduction of phosphonates, phosphinates, and phosphine oxides to primary, secondary, and tertiary phosphines using aluminum hydride reducing agents. The electrophilic reducing agents (iBu)2AlH and AlH3 were determined to be vastly superior to LiAlH4 for reduction selectivity and reactivity. Notably, it was determined that AlH3 is capable of reducing the exceptionally resistant tricyclohexylphosphine oxide, even though LiAlH4 and (iBu)2AlH were not. Using this new procedure, gram-scale reactions to synthesize a representative range of primary, secondary, and tertiary phosphines (including volatile phosphines) were achieved reproducibly with excellent yields and unmatched purity without the need for a purification step.
Rinehart, N. Ian,Kendall, Alexander J.,Tyler, David R.
supporting information
p. 182 - 190
(2018/02/06)

Oxazolidines as Intermediates in the Asymmetric Synthesis of 3-Substituted and 1,3-Disubstituted Tetrahydroisoquinolines
A diastereoselective mercury(II)-promoted intramolecular cyclization of unsaturated aldehyde via an oxazolidine to prepare C-3-substituted tetrahydroisoquinoline is disclosed. The C-3 stereogenic center is subsequently exploited to create the C-1 stereocenter by coordination of the nucleophilic reagent to the oxygen atom of oxazolidine. Both cis- and trans-1,3-disubstituted tetrahydroisoquinolines can be readily prepared. In addition, when a cationic rhodium complex was used, intramolecular hydroamination was effected, thus avoiding mercury(II) salts and demercuration. The reaction is general and works well using aliphatic and aromatic aldehydes.
Raghavan, Sadagopan,Senapati, Puspamitra
p. 6201 - 6210
(2016/08/16)

Synthesis and pharmacological evaluation of conformationally restricted κ-opioid receptor agonists
In order to obtain novel polar κ agonists the κ-pharmacophoric ethylenediamine structural element was embedded in a rigid bicyclic scaffold. The pyridooxazine system was selected since it contains polar O- and N-atoms in the 1- and 7-positions, respectively. An axially oriented pyrrolidine ring was attached at the 5-position and the dichlorophenylacetyl moiety was introduced at N-4. The key steps of the 11-step synthesis are a double Henry reaction of iminodiacetaldehyde 7 with nitromethane and the introduction of the azido moiety of 13 by Mitsunobu reaction of the alcohol 11 with Zn(N3)2·(pyridine)2. The X-ray crystal structure analysis of 17b shows a dihedral angle N(acyl)-C-C-N(pyrrolidine) of ?60.8(2)°, which is close to the postulated optimal angle. Moderate κ affinity was found for the secondary amine 17a (Ki = 132 nM) and the methyl derivative 17b (Ki = 266 nM). In the [35S]GTPγS assay the secondary amine 17a showed 28% agonistic activity compared to U-69,593. Although 17a and 17b contain all crucial κ-pharmacophoric elements, their κ affinity is rather low, which might be attributed to the unfavorable cis-orientation of the pyrrolidine ring and the dichlorophenylacetamido moiety and/or the additional O- and N-atoms in the 1- and 7-positions.
Wenker, Yvonne,Soeberdt, Michael,Daniliuc, Constantin,St?nder, Sonja,Schepmann, Dirk,Wünsch, Bernhard
p. 2368 - 2380
(2016/12/18)

Hydrogen release reactions of Al-based complex hydrides enhanced by vibrational dynamics and valences of metal cations
Hydrogen release from Al-based complex hydrides composed of metal cation(s) and [AlH4]- was investigated using inelastic neutron scattering viewed from vibrational dynamics. The hydrogen release followed the softening of translational and [AlH4]- librational modes, which was enhanced by vibrational dynamics and the valence(s) of the metal cation(s).
Sato,Ramirez-Cuesta,Daemen,Cheng,Tomiyasu,Takagi,Orimo
supporting information
p. 11807 - 11810
(2016/10/09)

An unexpected pentacarbonyl chromium complexation of a cyano group of the ABC core of cephalotaxine
A new penta-carbonyl chromium(0) complex of the type [Cr(CO)5(L)] (L = tetracyclic pyrrolobenzazepine unit 3) was surprisingly obtained by reacting [Cr(CO)3(naphthalene)] or [Cr(CO)3(tmtach)] with the tetracyclic pyrrolobenzazepine unit 3 in octane-ether/THF-solvent mixtures or acetone under ambient temperature or reflux. The new complex 13 has been characterized by spectral analysis including IR, 1H and 13C NMR data. For comparison purposes, the safrole-tricarbonyl chromium(0) complex 12 was prepared and characterized. X-ray diffraction analyses of both complexes were determined. Based on the above data, an octahedral structure has been assigned to the new complex 13.
Quteishat, Laith,Panossian, Armen,Le Bideau, Franck,Alsalim, Rana,Retailleau, Pascal,Troufflard, Claire,Rose, Eric,Dumas, Fran?oise
p. 35 - 42
(2015/01/09)

Lewis base complexes of AlH3: Prediction of preferred structure and stoichiometry
The structures adopted by a range of complexes AlH3·nL, (n = 1 or 2), have been explored in detail to identify the factors that determine the value of n, and whether a monomeric or dimeric arrangement is preferred for the 1 : 1 complexes. Single-crystal X-ray diffraction, vibrational and NMR spectroscopies, and thermal analysis data have been collected, DFT calculations have been performed for AlH3·nL species, and pKa values have been collated for a series of amine and phosphine ligands L. The pKa of the ligand L exerts an important influence on the type of complex formed: as the basicity of L increases, a monomeric structure is favoured over a dimeric arrangement. Dimeric amine complexes form if pKa a > 9.99. The steric requirements of L also influence the structural preference: bulky ligands with large cone angles (>163°) tend to favour formation of monomers, while smaller cone angles (3·NMe 2Et, AlH3·NMe3 and AlH 3·nEt2O. The Royal Society of Chemistry 2013.
Humphries, Terry D.,Munroe, Keelie T.,Decken, Andreas,McGrady, G. Sean
p. 6965 - 6978
(2013/08/25)

An improved two-step synthetic route to primary allylic alcohols from aldehydes
An improved two-step synthetic route to allylic alcohols from aldehydes has been developed. A modification of the HWE reaction in H2O-2-PrOH (1 : 1) and a convenient protocol to prepare AlH3 in THF from LiAlH 4 and n-BuBr are the key factors in the improvement.
Liu, Zheng,Gong, Yaqiong,Byun, Hoe-Sup,Bittman, Robert
p. 470 - 475
(2010/06/14)

Direct synthesis of unsolvated aluminum hydride involving Lewis and Bronsted acids
Unsolvated aluminum hydride has been synthesized by the direct reaction of aluminum bromide or sulfuric acid with an alkali metal tetrahydroaluminate at 90-102°C in pure toluene or in toluene containing 5-10 wt % diethyl ether. The reaction involving aluminum bromide yields a mixture of unsolvated aluminum hydride phases of poor quality. The reaction with sulfuric acid affords a single-phase product as α-AlH3 at ≤90°C.
Bulychev,Verbetskii,Storozhenko
p. 1000 - 1005
(2009/02/02)

TETRAHYDRO-5H-PYRIDO[2,3-D]AZEPINES AS 5-HT2C LIGANDS
Compounds according to Formula (I); wherein the radical R7 preferably represents a hetereocycle of 6 or 7 members and R4, R9-12 all preferably represent hydrogen atoms. These compounds and their pharmaceutical acceptable salts are used in pharmaceutical compositions and are useful for treating serotonin 5HT2C receptor mediated diseases. Processes to make such derivatives are as well disclosed therein.
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Page/Page column 58

(2008/06/13)

NOVEL 2,3-DIHYDROINDOLE COMPOUNDS
The invention relates to compounds of the formula I wherein the variables are as defined in the claims. The compounds are useful in the treatment of a disease where a D4 receptor and/or a 5-HT 2A receptor is implicated.
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Page/Page column 7

(2008/06/13)

NOVEL 2,3-DIHYDROINDOLE COMPOUNDS
The invention relates to compounds of the formula I, wherein the variables are as defined in the claims. The compounds are useful in the treatment of a disease where a D4 receptor and/or a 5-HT2A receptor is implicated.
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(2010/11/26)

Infrared spectra of aluminum hydrides in solid hydrogen: Al2H4 and Al2H6
The reaction of laser-ablated Al atoms and normal-H2 during co-deposition at 3.5 K produces AlH, AlH2, and AlH3 based on infrared spectra and the results of isotopic substitution (D2, H2 + D2 mixtures, HD). Four new bands are assigned to Al2H4 from annealing, photochemistry, and agreement with frequencies calculated using density functional theory. Ultraviolet photolysis markedly increases the yield of AlH3 and seven new absorptions for Al2H6 in the infrared spectrum of the solid hydrogen sample. These frequencies include terminal Al-H2 and bridge Al-H-Al stretching and AlH2 bending modes, which are accurately predicted by quantum chemical calculations for dibridged Al2H6, a molecule isostructural with diborane. Annealing these samples to remove the H2 matrix decreases the sharp AlH3 and Al2H6 absorptions and forms broad 1720 ± 20 and 720 ± 20 cm-1 bands, which are due to solid (AlH3)n. Complementary experiments with thermal Al atoms and para-H2 at 2.4 K give similar spectra and most product frequencies within 2 cm-1. Although many volatile binary boron hydride compounds are known, binary aluminum hydride chemistry is limited to the polymeric (AlH3)n solid. Our experimental characterization of the dibridged Al2H6 molecule provides an important link between the chemistries of boron and aluminum.
Wang, Xuefeng,Andrews, Lester,Tam, Simon,DeRose, Michelle E.,Fajardo, Mario E.
p. 9218 - 9228
(2007/10/03)

Indole derivatives useful for the treatment of CNS disorders
An indole derivative having the formula wherein a) Y1 is N, which is bound to Z, Z and Y2 are selected from CH2, CO, CS, SO and SO2; provided that at least one of Z and Y2 is CH2; Y3is O, S or CHR7and Y4is O, S or CHR8, provided that only one of Y3 and Y4 is O or S; b) Y2 is N, which is bound to Z, Z and Y1 are selected from CH2, CO, CS, SO and SO2; provided that at least one of Z and Y1 is CH2; Y3is CHR7 and Y4is O, S or CHR8; c) Y2 is N, which is bound to Z, Z and Y3 are selected from CH2, CO, CS, SO and SO2 provided that at least one of Z and Y3 is CH2; Y1 is CHR6 and Y4 is O, S or CHR8; W is a bond, O, S, CO, CS, SO or SO2; n is 0-5, m is 0-5 and n+m is 1-6; provided that when W is O or S, then n≧2 and m≧1; when W is CO, CS, SO or SO2, then n≧1 and m≧1; X is C, CH or N, provided that when X is C, the dotted line indicates a bond, and when X is N or CH, the dotted line indicates no bond; one of R1, R2, R3 and R4 forms a bond to X and the others of R1, R2, R3, R4 and R5 and R9-R12 are independently selected from hydrogen, halogen, cyano, nitro, amino, hydroxy, C1-6-alkyl-amino, di-( C1-6-alkyl )-amino, C1-6-alkyl, C2-6-alkenyl, C2-6-alkynyl, C1-6 alkoxy, C1-6-alkylthio, C1-6-alkyl substituted with hydroxy or thiol, C3-8-cycloalkyl, C3-8-cycloalkyl-C1-6-alkyl, acyl, thioacyl, trifluoromethyl, trifluoromethylsulfonyl or C1-6 alkylsulfonyl; R is hydrogen, C1-6-alkyl, C2-6-alkenyl, C2-6-alkynyl, C1-6-alkyl substituted with hydroxy or thiol, C3-8-cycloalkyl, C3-8-cycloalkyl-C1-6-alkyl, acyl, thioacyl, trifluoromethylsulfonyl and C1-6 alkylsulfonyl; or pharmaceutically acceptable salts thereof. The compounds of the invention are potent dopamine D4 ligands.
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(2010/02/06)

Oligophospane Ligands, XXVII. - RuH2: Formation, Protonation, CO2 Insertion, and Oxidative Addition of Benzene
An extremely labile polyhydric aluminato species of composition x (2) was isolated as an intermediate of the reaction between RuCl2(pp3) and LiAlH4 in THF, which leads to RuH2(pp3) (1) as the final product . 1 reacted with HBF4 to produce BF4 (3); the conversion of 1 into the trihydrido derivative BF4 failed.Exposure of 1 to CO2 yielded the formato complex RuH(pp3) (4).Photolysis of 1 in C6D6 gave RuD(C6D5)(pp3) as the exclusive organometallic product, which strongly suggests that the photochemical formation of RuH(C6H5)(pp3) (5) from 1 and C6H6 proceeds by oxidative addtion of benzene C-H bonds to the coordinatively unsaturated fragment Ru(pp3).The molecular structure of 5 was determined by X-ray diffraction.
Antberg, Martin,Dahlenburg, Lutz,Frosin, Kay-Michael,Hoeck, Nils
p. 859 - 864
(2007/10/02)

Metal tetrahydridoborates and (tetrahydroborato)metalates. 10. NMR study of the systems AlH3/BH3/THF and LiAlH4/BH3/THF
The systems AlH3/BH3/THF and LiAlH4/BH3/THF have been investigated by means of 11B and 27Al NMR spectroscopy. The NMR spectra indicate equilibria of the types AlH3 + nBH3 ? AlH3-n(BH4)n and 2AlH3-n(BH4)n ? AlH3-(n+1)(BH4)n+1 + AlH3-(n-1)(BH4)n-1 with all Al species and BH3 coordinated with THF. An even more complex situation holds for the LiAlH4/BH3/THF system. The species formed are LiBH4 and AlH3-n(BH4)n in equilibrium with LiAlH3-n(BH4)n+1. The equilibria are shifted toward the (tetrahydroborato)aluminates more strongly with increasing n and decreasing temperatures. At higher temperatures a rapid BH4- exchange prevails. Moreover, at high n values it is not only THF that competes with Al-H for BH3 but also BH4- which gives rise to B2H7-.
N?th, Heinrich,Rurl?nder, Robert
p. 1062 - 1072
(2008/10/08)