Michel Rajzmann

  • Citations Per Year
Learn More
Ab initio and semiempirical quantum mechanical calculations were performed to study the electronic spectra of spiroxazine photochromic compounds as well as the corresponding photoisomers. Ground-state geometries were optimized based on density functional theory (DFT). Excitation energies of the different forms were calculated using the time-dependent(More)
The reactions between electron-rich 2-aza-dienes and α-oxo-ketenes derived from the Wolff rearrangement of 2-diazocycloalkane-1,3-diones chemo- and regioselectively produced spiro hydropyrid-4-ones with good to excellent diastereoselectivities. These reactions are likely to proceed via a domino Wolff/Friedel-Crafts/intramolecular Mannich process. Prolonged(More)
The Al(OTf)(3)-catalyzed cycloisomerization of unactivated unsaturated alcohols was studied from experimental and theoretical points of view. A series of cyclic ethers was obtained in excellent yields and regioselectivities. This catalyst system provides one of the most straightforward routes to cyclic ethers with Markovnikov-type regioselectivity under(More)
The synthetic utility of γ-alkylidenebutenolides is demonstrated as highly competent dipolarophile partners in both intra- and intermolecular rhodium(II)-catalyzed 1,3-dipolar cycloaddition reactions. The strength of this approach lies in the formation of spiro[6,4]lactone moieties with the concomitant construction of quaternary spiro stereocenters.(More)
In this work, we have performed quantum calculations, using cluster models, in order to study the reactivity of the aluminum and oxygen sites of the g-alumina surface. Water, hydrogen sul®de and carbon monoxide molecules are employed as the test molecules for our cluster models. It is found that the tricoordinated aluminum sites of the surface are the(More)
UV- and IR-induced photoisomerization of acetylacetone trapped in a nitrogen matrix at 4.3 K have been carried out using a tunable optical parametric oscillator type laser, or a mercury vapor lamp, coupled with Fourier Transform IR and UV spectroscopies. After deposition, the main form present in the cryogenic matrix is that chelated (enol). Upon UV(More)
Nucleophilic addition of pyridines to benzyne generates zwitterionic adducts that evolve by a rapid intramolecular proton shift to produce the corresponding pyridine carbenes, N-phenyl pyrid-2-ylidenes. In the presence of electrophilic ketones (isatin derivatives), the pyridylidenes can further react by an original bis-arylation reaction of the carbonyl(More)
Cryogenic matrix isolation experiments have allowed the measurement of the UV absorption spectra of the high-energy non-chelated isomers of acetylacetone, these isomers being produced by UV irradiation of the stable chelated form. Their identification has been done by coupling selective UV-induced isomerization, infrared spectroscopy, and harmonic(More)
  • 1