Ph (3b), H (3c), Me (3d)). The formation of complexes 3a-d and 4a-c proceeds through an intramolecular cycloaddition of the CdC allyl and C R dC β bonds in the intermediate allenylidene complexesThe allenylidene complex [Ru(η 5 -C 9 H 7 )(dCdCdCPh 2 ){κ 1 (P)-Ph 2 PCH 2 CHdCH 2 }(PPh 3 )][PF 6 ] (5) has been isolated from the reaction of 2a with 1,1diphenyl-2-propyn-1-ol in CH 2 Cl 2 . The deprotonation of complexes 3a-d and 4a with potassium tert-butoxide gives rise to the neutral complexes [Ru(η 5 -C n H m ){κ 2 (P,C)-{CdC-

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[L = CO, X = SbF 6 , R = CH 2 CH=CH 2 (3a), CH 2 CH 2 CH=CH 2 (3b); L = PPh 3 , X = PF 6 , R = CH 2 CH 2 CH=CH 2 (4b)] have been prepared by treatment of the complexes 1a,b and 2b with a halide abstractor such as AgSbF 6 or NaPF 6 , respectively. Deprotonation reactions of

Conditions for a first oxidative conversion of alkenes into 2-amino ketones are described, which yield racemic products within a direct oxidation pathway and 2-amino ketones with up to 99% enantiomeric excess from the corresponding enantiopure amino alcohols.

The cyclopentadienyl-containing complex [Ru(η5-C5H5)(MeCN){κ3(P,C,C)-Ph2PCH2CHCH2}][PF6] (1) reacts with allenes, giving regioselectively the η2-allene complexes [Ru(η5-C5H5)(MeCN){κ(P)-Ph2PCH2CHCH2}(η2-CH2CCR1R2)][PF6] [R1 = R2 = Me (3); R1 = H, R2 = Ph (4); R1R2 = −(CH2)5– (5)]. On the other hand, the reaction of the pentamethylcyclopentadienyl-containing complex [Ru(η5-C5Me5)(MeCN){κ3(P,C,C)-Ph2PCH2CHCH2}][OTf] (2) with allenes yields regio- and stereoselectively the complexes [Ru(η5-C5Me5){κ(P),η4-Ph2PCH2CHCHC(R1R2)CHCH2}][OTf] [R1 = R2 = Me (6); R1 = H, R2 = Ph (7); R1R2 = −(CH2)5– (8)] via the intermolecular coupling of allene and allyldiphenylphosphine ligands. The intermediate complex [Ru(η5-C5Me5)(MeCN){κ(P)-Ph2PCH2CHCH2}{η2-CH2CCMe2}][OTf] (9) has been spectroscopically characterized. The structure of complex [Ru(η5-C5Me5){κ(P),η4-Ph2PCH2CHCHC(Me)2CHCH2}][{3,5-(CF3)2C6H3}4B] (6a) has been resolved by X-ray diffraction analysis.

Partial oxidation of CH 4 to C 2 H 4 and C 2 H 6 (CH 4 coupling) over a nonstoichiometric catalyst Li 0.9 Ni 0.5 Co 0.5 O 2-x , in which Li + cations and lattice oxygen anions are mobile under certain conditions, was investigated. The reaction spectrum was recorded dynamically and illustrated a considerable quantity of C 2 H 4 and C 2 H 6 formation above 700°C. Activation energies up to 800°C were estimated based on the Arrhenius empirical model. The results of both TPRS (temperature programmed reaction spectrum) and TPSR (temperature programmed surface reaction) indicate that active surface oxygen leads to the production of C 2 H 4 and C 2 H 6 , while CO 2 is produced from both gaseous and surface oxygen. The spectra also suggest that at least two types of lattice oxygen are responsible for the formation of C 2 s. TPR (temperature programmed reduction) showed two H 2 consumption peaks. However, TPO (temperature programmed oxidation) of pre-reduced samples showed five oxidative peaks, none of them representing metallic Ni or Co. The active site is proposed to contain lattice oxygen.Since the pioneering work by Keller and Bhasin (7), the oxidative coupling of methane (OCM) to ethane, ethylene and higher hydrocarbons has attracted the attention of many scientists from academia and industries, as shown in a number of review papers (2-4). The kinetics and mechanism of OCM on a wide variety of catalysts have been the subject of many publications in recent years (5)(6)(7)(8). It is generally agreed that C 2 H 6 formation occurs via dehydrogenation of the CH 4 molecule on the catalytic active site, followed by gas phase coupling of the resulting methyl radicals. The types of active sites involved in the reaction vary with the catalysts and determine the reaction pathway for the formation of the undesired deep oxidation products CO and C0 2 (9-11). Furthermore, since the CH 4 molecule can be activated via adsorbed oxygen, lattice

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