Primary alcohols undergo oxidative condensation upon treatment with RuH2(PPh3)4 catalyst to give esters and molecular hydrogen. Similarly, 1,4-and 1,5-diols can be converted into the corresponding 7-and -lactones, respectively. The lactonization is greatly enhanced by accepting hydrogen with an appropriate hydrogen acceptor such as acetone. Primary alcohols are oxidized chemoselectively in the presence of secondary alcohols to give

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phenylphosphino)ethane (dppe) (entry 4), although addition of 1.3bis(diphenylphosphino)propane (dppp) retards the reactions.5Michael addition of nitriles to alkenes proceeds efficiently at room temperature under neutral conditions. Representative results are shown in Table I. The reaction of ,/3-unsaturated carbonyl compounds gives Michael adducts without contamination by the corresponding aldol products (entries 5 and 6).One important feature of the present reaction is the chemoselective reaction of nitriles with either carbonyl compounds or Michael acceptors in the presence of other active methylene compounds. Indeed, the RuH2(PPh3)4-catalyzed reaction of benzaldehyde with an equimolar mixture of ethyl cyanoacetate (3, pKa > 9) and acetylacetone, which has a similar p value (pAa = 9.0),6 gave ethyl (£')-2-cyano-3-phenylpropanoate (4, 80%) exclusively. In contrast, the reaction of benzaldehyde with the same mixture in the presence of a conventional base such as KOH and AcONH4 gave a mixture (3:1) of 4 and 3-benzylidene-2,4pentanedione. Similarly, the treatment of crotononitrile with an equimolar mixture of 3 and nitroethane (p/fa = 8.6) gave ethyl 2.4dicyano-3-methylbutanoate chemoselectively.The utility of the present method has also been indicated by the high diastereoselectivity of the Michael additions. When cyano ester 5, which can be readily obtained by the catalytic Michael

The ruthenium-catalysed oxidation of secondary amines with t-butyl hydroperoxide under mild conditions affords the corresponding imines in high yields.Transition metal-catalysed reactions of amines are of biological and synthetic importance. Low-valent transition metals react with amines with and without N-H bonds to give iminel and iminium ion metal hydride intermediates,* respectively.During our studies on the oxidation of metal hydrides, we found that ruthenium(ii)-catalysed oxidation of secondary amines with t-butyl hydroperoxide gives the corresponding imines efficiently [equations (1) and ( 2)]. This is the first

The M7A-03 gas turbine, an 8 MW class, single shaft gas turbine, is the latest model of the Kawasaki M7A series. Because of the high thermal efficiency and the high exhaust gas temperature, it is particularly suitable for distributed power generation, cogeneration and combined-cycle applications. About the development of M7A-03 gas turbine, Kawasaki has taken the experience of the existing M7A-01 and M7A-02 series into consideration, as a baseline. Furthermore, the latest technology of aerodynamics and cooling design, already applied to the 18 MW class Kawasaki L20A, released in 2000, has been applied to the M7A-03. Kawasaki has adopted the design concept for achieving reliability within the shortest possible development period by selecting the same fundamental engine specifications of the existing M7A-02 – mass air flow rate, pressure ratio, TIT, etc. However, the M7A-03 has been attaining a thermal efficiency of greater than 2.5 points higher and an output increment of over 660 kW than the M7A-02, by the improvement in aerodynamic performance of the compressor, turbine and exhaust diffuser, improved turbine cooling, and newer seal technology. In addition, the NOx emission of the combustor is low and the M7A-03 has a long service life. These functions make long-term continuous operation possible under various environmental restraints. Lower life cycle costs are achieved by the engine high performance, and the high-reliability resulting from simple structure. The prototype M7A-03 gas-turbine development test started in the spring of 2006 and it has been confirmed that performance, mechanical characteristics, and emissions have achieved the initial design goals.