Über Eigenwerte und Eigenfunktionen einer Klasse von nichtselbstadjungierten Randwertproblemen

Ohne Zusammenfassung     

Über das asymptotische Verhalten von Lösungen der linearen DifferentialgleichungM [y]=λN [y] für groß Werte von |λ|

Ohne Zusammenfassung     

Experimental investigations on gain and maximum output of the He-Ne laser

The influence of homogeneous and inhomogeneous line broadening on gain saturation, optimum decoupling and output power of the He-Ne laser is investigated experimentally. It is shown that both types of broadening are present, and that the output power is essentially determined by the homogeneous part if the gas pressure is chosen for maximum output. Experimental results are obtained forλ=0.633 μ andλ=1.15 μ and tubes of different diameters and lengths.     

Phase-locked ultrashort pulse trains at separate and independently tunable wavelengths

The generation and characterization of femtosecond pulses at three independently tunable visible wavelengths is reported. Selected spectral portions of a common continuum generated in sapphire are amplified in noncollinear optical parametric amplifiers. The phase relation of the pulse trains is analyzed with a nonlinear interferometer based on coherent anti-Stokes Raman scattering and is found to be locked to better than 250 mrad rms. Small spectral shifts of the pulses lead to interference behavior that is consistent with 1 kHz frequency combs.     

A Novel Stereoselective Synthesis of <Emphasis Type="Italic">cis</Emphasis>-Configured Erythrinane and Erythrinane Type Analogues

Summary. N-Alkylation of certain angularly substituted heterocycles by C₂- and C₃-units provided appropriate precursors to construct stereoselectively the erythrinanone and several erythrinanone type analogues by intramolecular Friedel-Crafts acylation. The resulting aromatic ketones were catalytically reduced affording the corresponding parent frameworks including the hitherto unknown tetracyclus A-norschelhammerane. On the other hand, the stereoselective reduction of the carbonyl moiety offered a convenient approach to 11-hydroxylated erythrinanes with the natural occurring -configuration. The structures and the stereochemistry of the target compounds were proved by NMR spectroscopy.Part of PhD thesis, LMU München, D     

A Convenient Synthesis of 1-Benzyl-1,2,3,4-tetrahydroisoquinolines by Combined Strecker/Bruylants Reaction

Summary. Strecker reaction of iodophenethylamines with phenylacetaldehydes afforded the corresponding -aminonitriles, which on treatment with i-propyl magnesium chloride underwent a Bruylants reaction to give the title compounds. Their structures were deduced by NMR and by an independent preparation starting from papaverine. The educts were easily available by standard procedures.