Results 251 to 260 of about 12,432 (295)

Enantioselective synthesis of oxa-spiro compounds

Tetrahedron Letters, 1989
Abstract Optically active compound 10b, efficiently prepared from imine 8b, was transformed into oxa-spiro derivatives 15 and 16 .
Didier Desmaële, Jean d'Angelo
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Ultrafast optical dynamics of spiro-compounds

Synthetic Metals, 2001
We report on time-resolved measurements of spiro-type molecules in the ps- and fs-timescale. Due to the orthogonality of the transition dipoles of two identical moieties connected through a spiro-atom, one expects these compounds to show two perpendicular, degenerate states that may enter into a complex free evolution upon fs excitation.
Milota, Franz, Warmuth, Christian, Tortschanoff, Andreas, Sperling, Jaroslaw, Fuhrmann, Thomas, Salbeck, Josef, Kauffmann, Harald   +6 more
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Electronic properties of spiro compounds for organic electronics

The Journal of Chemical Physics, 2012
The electronic properties of p-type, n-type, and ambipolar spiro materials have been investigated using a combination of photoemission spectroscopy, electron energy-loss spectroscopy, and density functional based calculations. Our results provide insight into the occupied density of states as well as the electronic excitation spectra.
Benjamin, Mahns, Friedrich, Roth, Mandy, Grobosch, Susi, Lindner, Martin, Knupfer, Tobat P I, Saragi, Thomas, Reichert, Josef, Salbeck, Torsten, Hahn   +8 more
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A New Spiro Compound from Caragana acanthophylla

Chemistry of Natural Compounds, 2017
The new spiro compound 1-carbonyl-3-methoxy-2,4-diene-spiro[5,7]-14,15-dihydroxynaphthalene (1) and four known compounds [calycosin (2), psoracinol (3), octadecyl caffeate (4), (–)-syringaresinol (5)] were isolated from the aerial part of Caragana acanthophylla. The molecular structures were determined using PMR, 13C NMR, 2D, and mass spectra.
L. Maihesuti, P. Lan, M. Imerhasan, K. A. Eshbakova, X. Jia   +4 more
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Preparation and ESR of phosphorus spiro compounds. Part III

Recueil des Travaux Chimiques des Pays-Bas, 1974
AbstractThe synthesis of 2,2′‐biphenylenediphenylphosphonium, 2,2′‐biphenylenephenylbenzylphosphonium and 2,2′‐biphenylenephenyl(p‐nitrophenyl)phosphonium salts is described. The related phosphoranyl radicals I, IV and V, generated by electrochemical reduction, are measured by ESR spectroscopy.
Rothuis, R., Font Freide, J.J.H.M., van Dijk, J.M.F., Buck, H.M.   +3 more
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Chiral Separation of Spiro-compounds and Determination Configuration

Chemical Research in Chinese Universities, 2008
Abstract Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synthesizing active enantiomers, or as surface modifiers on silica particles to resolve entantiomers.
Y LIANG, J GUO, X LIU, R WEI
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Carbon‐13 magnetic resonance study of spiro compounds

Organic Magnetic Resonance, 1974
AbstractA large series of cyclohexane and cyclopentane spiro compounds has been studied by carbon‐13 NMR. Increments have been derived in terms of α, β, γ spiro substituent effects, one ring being considered as the substituent of the other. As usual α and β effects are paramagnetic and γ effects are diamagnetic. They are compared with the corresponding
Zimmermann, Daniel, Ottinger, Robert, Reisse, Jacques, Christol, Henri, Brugidou, J.   +4 more
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Tetracyclo[3,3,1,02,4,02,8]nonane. A strained spiro-compound

Journal of the Chemical Society, Chemical Communications, 1974
Reaction of the dibromocarbene adduct of 4-vinylcyclohexene with methyl-lithium at –48° to –50° gives the spiro-compound (IV), but by modifying the reaction condition a ready route to the exo-tricyclo-[3,3,1,02,4] ring system is obtained.
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Cannabispirone and cannabispirenone, two naturally occurring spiro-compounds

Tetrahedron, 1976
Abstract Structure elucidation of two naturally occurring acidic compounds from Cannabis gave two spiro-compounds. The spectroscopic properties ( 1 H-NMR, 13 C-NMR, MS, IR and UV) and interpretation of these spectra are given.
C.A.L. Bercht, J.P.C.M. van Dongen, W. Heerma, R.J.J. Ch. Lousberg, F.J.E.M. Küppers   +4 more
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ChemInform Abstract: CANNABIS. XXII. SYNTHESIS OF SPIRO‐COMPOUNDS

Chemischer Informationsdienst, 1981
AbstractAus dem Indanon (I) entsteht mit Methoxymethylen‐phosphoran das Olefin (II), das zum Aldehyd (III) verseift wird.
J. NOVAK, C. A. SALEMINK
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