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Université de Neuchâtel

[6-(Hydroxymethyl)pyridin-2-yl]methyl ferrocene-1-carboxylate

Auzias, Mathieu ; Süss-Fink, Georg ; Therrien, Bruno

In: Acta Crystallographica Section E, 2011, vol. E67, no. 11, p. m1618

The crystal structure of the title ferrocene derivative, [Fe(C5H5)(C13H12NO3)], shows strong intermolecular O-H...N hydrogen bonds between the alcohol function and the pyridine group of a neighbouring molecule, while the pyridine function forms another hydrogen bond with the alcohol function of another neighbouring molecule, resulting in the...

Université de Neuchâtel

5-Hydroxyalkyl derivatives of tert-butyl 2-oxo-2,5-dihydro-1H-pyrrole-1-carboxylate: diastereoselectivity of the Mukaiyama crossed-aldol-type reaction

Vallat, Oliver ; Buciumas, Ana-Maria ; Neier, Reinhard ; Stoeckli-Evans, Helen

In: Acta Crystallographica Section C : Crystal Structure Communications, 2009, vol. C65, no. 4, p. o171-o175

The title compounds, rac-(1'R,2R)-tert-butyl 2-(1'-hydroxyethyl)-3-(2-nitrophenyl)-5-oxo-2,5-dihydro-1H-pyrrole-1-carboxylate, C17H20N2O6, (I), rac-(1'S,2R)- tert-butyl 2-[1'-hydroxy-3'-(methoxycarbonyl)propyl]-3-(2-nitrophenyl)-5-oxo-2,5-dihydro-1H-pyrrole-1-carboxylate,...

Université de Neuchâtel

4,4-Bis(1H-pyrrol-2-yl)pentanol

Journot, Guillaume ; Neier, Reinhard ; Stoeckli-Evans, Helen

In: Acta Crystallographica Section E : Structure Reports Online, 2010, vol. E66, no. 2, p. o393, sup1-8

The title achiral compound, C13H18N2O, crystallized in the chiral monoclinic space group P21. The pyrrole rings are inclined to one another by 62.30 (11)°, and the propanol chain is in an extended conformation. In the crystal, the two pyrrole NH groups are involved in intermolecular N-H ··· O hydrogen bonds, leading to the formation of a...

Université de Neuchâtel

2D laser collimation of a cold Cs beam induced by a transverse B field

Plimmer, M. ; Castagna, N. ; Di Domenico, G. ; Thomann, Pierre ; Taichenachev, A. V. ; Yudin, V. I.

In: JETP Letters, 2005, vol. 82, no. 1, p. 17-21

We describe transverse collimation of a continuous cold cesium beam (longitudinal temperature 75 μK) induced by a two-dimensional, blue-detuned near-resonant optical lattice. The mechanism described for a lin-||-lin configuration is made possible by the application of a transverse magnetic field B. The phenomenon described differs from gray molasses, for which any small...

Université de Neuchâtel

(1S,3S,7R)-3-methyl-α-himachalene from the male sandfly Lutzomyia longipalpis (Diptera: Psychodidae) induces neurophysiological responses and attracts both males and females

Spiegel, C.N. ; Jeanbourquin, P. ; Guerin, Patrick M. ; Hooper, A.M. ; Claude, S. ; Tabacchi, R. ; Sano, S. ; Mori, K.

In: Journal of Insect Physiology, 2005, vol. 51, no. 12, p. 1366-1375

Lutzomyia longipalpis adult males form leks on or near hosts and release (1S,3S,7R)-3-methyl-α-himachalene from their tergal glands to lure females to the same site for mating and feeding. Here we have examined whether the male-produced attractant could also serve as a male aggregation stimulus. High resolution chiral capillary gas chromatography analysis of male...

Université de Neuchâtel

2,3,4,7-Tetrahydro-1H-inden-2-ol: synthesis, molecular structure and coordination chemistry

Vieille-Petit, Ludovic ; Therrien, Bruno ; Süss-Fink, Georg

In: Polyhedron, 2004, vol. 23, no. 4, p. 687-691

2,3,4,7-Tetrahydro-1H-inden-2-ol (1) has been synthesised by Birch reduction of indan-2-ol. A single-crystal X-ray structure analysis of 1 shows the compound to exist as hydrogen-bonded polymers along the c-axis due to the presence of a series of hydrogen-bonds between hydroxo functions. The ferrocene ester derivatives, ferrocene carboxylic acid...

Université de Neuchâtel

1,3-Dipolar cycloadditions : click chemistry for a new synthesis of 5-substituted tetrazoles and applications in organocatalysis

Aureggi, Valentina ; Neier, Reinhard (Dir.) ; Sedelmeier, Gottfried (Codir.)

Thèse de doctorat : Université de Neuchâtel, 2007 ; Th.1959.

Les besoins récents en chimie organique de synthèse appliquée focalisent les efforts des chercheurs au développement de nouvelles voies efficaces et versatiles pour la préparation de molécules bioactives, en prenant en comptes en particulier les critères économiques et environnementaux. Nous avons développé une méthode novatrice et écologique pour la préparation de tetrazoles...

Université de Neuchâtel

An 8-bit low-power ADC array for CMOS image sensors

Tanner, Steve ; Heubi, Alexandre ; Ansorge, Michael ; Pellandini, Fausto

In: IEEE International Conference on Electronics, Circuits and Systems, 1998, vol. 1, p. 147-150

The paper presents an original analog-to-digital converter (ADC) array meeting the constraining requirements in resolution, speed, size, and low power consumption of high-performance low-cost video cameras. The converter array is based on ADC cells relying on a cyclic redundant signed digit (RSD) algorithm supporting comparators with extended tolerance. A prototype ADC array composed of 32...

Université de Fribourg

The 2003 heat wave in Europe: A shape of things to come? An analysis based on Swiss climatological data and model simulations

Beniston, Martin

In: Geophysical Research Letters, 2004, vol. 31, p. L02202

The 2003 heat wave that affected much of Europe from June to September bears a close resemblance to what many regional climate models are projecting for summers in the latter part of the 21st century. Model results suggest that under enhanced atmospheric greenhouse-gas concentrations, summer temperatures are likely to increase by over 4°C on average, with a corresponding increase in the...

EPFL

Ab initio study of interface states at metal contacts to III-IV semiconductors

Maxisch, Thomas ; Baldereschi, Alfonso (Dir.)

Thèse sciences Ecole polytechnique fédérale de Lausanne EPFL : 2003 ; no 2890.