Intrinsic reactivity of metal–hydroxide complexes: O–H bond activation and adduct formation in gas-phase reactions of Cp2ZrOH+

The gas-phase reactions of methane with the platinum(II) ions PtX+ with X = H, Cl, Br, and CHO are studied by mass spectrometry. The PtX+ ions are generated by electrospray ionization of methanolic solutions of hexachloroplatinic acid and hexabromoplatinic acid, respectively. Small to moderate intramolecular kinetic isotope effects determined for the CH(D) bond activation of CH2D2 suggest that the activation of methane by gaseous PtX+ cations is subject to thermochemical control by the product channels. In addition, the PtCl2+ cation is also able to activate methane, whereas PtCl3+ is unreactive under the conditions chosen. Key words: gas-phase reactions, mass spectrometry, methane activation, platinum bromide, platinum chloride.

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Gas Phase Adduct Reactions in MOCVD Growth of GaN

MRS Proceedings ◽

10.1557/proc-395-97 ◽

1995 ◽

Vol 395 ◽

Cited By ~ 2

Author(s):

A. Thon ◽

T.F. Kuech

Keyword(s):

Activation Energy ◽

Gas Phase ◽

Decomposition Temperature ◽

Adduct Formation ◽

Gas Phase Reactions ◽

Flow Tube ◽

Exponential Factor ◽

First Order ◽

Mocvd Growth ◽

Tube Reactor

ABSTRACTGas phase reactions between trimethylgallium (TMG) and ammonia were studied at high temperatures, characteristic to MOCVD of GaN reactors, by means of insitu mass spectroscopy in a flow tube reactor. It is shown, that a very fast adduct formation followed by elimination of methane occurs. The decomposition of TMG and the adduct - derived compounds are both first order and have similar apparent activation energy. The pre-exponential factor of the adduct decomposition is smaller, and hence is responsible for the higher full decomposition temperature of the adduct relative to that of TMG.

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Gas-phase reactions of niobium(1+) and tantalum(1+) with alkanes and alkenes. Carbon-hydrogen bond activation and ligand-coupling mechanisms

Inorganic Chemistry ◽

10.1021/ic00317a024 ◽

1989 ◽

Vol 28 (18) ◽

pp. 3511-3518 ◽

Cited By ~ 72

Author(s):

Steven W. Buckner ◽

Timothy J. MacMahon ◽

Gary D. Byrd ◽

Ben S. Freiser

Keyword(s):

Hydrogen Bond ◽

Gas Phase ◽

Bond Activation ◽

Gas Phase Reactions ◽

Carbon Hydrogen Bond Activation ◽

Coupling Mechanisms

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Oxidative dealkylation of aromatic amines by "bare" FeO+ in the gas phase

Canadian Journal of Chemistry ◽

10.1139/v99-065 ◽

1999 ◽

Vol 77 (5-6) ◽

pp. 774-780 ◽

Cited By ~ 7

Author(s):

Mark Brönstrup ◽

Detlef Schröder ◽

Helmut Schwarz

Keyword(s):

Gas Phase ◽

Bond Activation ◽

Isotope Effects ◽

Gas Phase Reactions ◽

Electron Transfer Mechanism ◽

Gas Phase Chemistry ◽

Kinetic Isotope ◽

Phase Chemistry ◽

Cytochrome P 450 ◽

Mass Spectrometric Techniques

The gas-phase oxidations of aniline, N-methylaniline, and N,N-dimethylaniline by FeO+ cation are examined by using mass spectrometric techniques. Although bare FeO+ is capable of hydroxylating aromatic CH bonds, the fate of the oxidation of arylamines is determined by docking of the FeO+ unit at nitrogen. The major reactions of the metastable aniline/FeO+ complex are losses of molecular hydrogen, ammonia, and water, all involving at least one N-H proton. N-alkylation results in a complete shift of the course of the reaction. The unimolecular processes observed can be regarded as initial steps of an oxidative dealkylation of the amines mediated by FeO+. More detailed mechanistic insight is obtained by examining the CH(D) bond activation of N-methyl-N-([D3]-methyl)aniline by bare and ligated FeO+ species. The gas-phase reactions of FeO+ with methylanilines show some similarities to the enzymatic dealkylation of amines by cytochrome P-450. The kinetic isotope effects observed experimentally suggest an electron transfer mechanism for the gas-phase reaction.Key words: mass spectrometry, gas-phase chemistry, iron, dealkylation, N,N-dimethylaniline.

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