Results 161 to 170 of about 3,055 (208)

Isoxazoline

2005
The first part of the presented work deals with the enantioselective synthesis of isoxazolines. The synthetic approach involves the asymmetrically catalysed 1,3-dipolar cycloaddition of nitrones to acetylenes. Therefore electrondeficient mono- and bifunctionalysed as well as electronrich triplebond systems, in combination with electronrich and ...
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Solid-Phase Synthesis of Isoxazolines

Journal of Combinatorial Chemistry, 2002
The polymer-supported synthesis of isoxazolines is described via nitrile oxide intermediates, starting from primary nitroalkanes in a one-pot process.
S, Chandrasekhar, Abbas, Raza, M Venkat, Reddy, J S, Yadav   +3 more
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2-isoxazoline derivatives—VIII

Tetrahedron, 1974
Abstract The reaction of nitrile oxides with tropone yields a mixture of at least 8 products, the structures of which are based on spectral and chemical evidence. Both addition of the 1,3-dipole to the carbonyl group and cycloadditions to the CC double bonds system have been observed.
C. De Micheli, R. Gandolfi, P. Grünanger   +2 more
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3‐H‐isoxazolin‐5‐ones

Journal of Heterocyclic Chemistry, 1967
Abstract4‐Alkyl and 4‐phenyl isoxazolin‐5‐ones were prepared. The 4‐alkyl compounds were found to isomerize easily to α‐cyano carboxylic acids. The acidity and the tautomeric composition of the compounds prepared arc surveyed and compared to the results of the previous literature.
DE SARLO, FRANCESCO, G. DINI
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Photochemistry of condensed isoxazolines

Monatshefte für Chemie Chemical Monthly, 1994
The condensed bridged isoxazolines4 are rearranged on irradiation with a low-pressure mercury lamp exclusively into condensed derivatives of tetrahydropyridine5. The selectivity of the rearrangement is due to a stabilization of the biradical8 by the overlap of the radical-electrons with π-electrons of the C=C double bond and the heterocyclic ring ...
V. Ondruš, L'. Fišera, N. Prónayová
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5-Amino-2-isoxazolines

Chemistry of Heterocyclic Compounds, 1990
The corresponding previously unknown 5-amino-2-isoxazolines were obtained by the action of ammonia and primary amines on acetylacetone monoxime and on 3,4,4-trimethyl-5-methylene-2-isoxazoline. Their structure was confirmed by NRM spectroscopy.
K. N. Zelenin, A. Yu. Ershov
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Asymmetric synthesis of chiral spiro bis(isoxazoline) and spiro (isoxazole–isoxazoline) ligands

Tetrahedron: Asymmetry, 2010
Abstract Asymmetric synthesis of novel chiral ligands, bis(isoxazoline) on a spiro[4.4]nonane scaffold and isoxazole–isoxazoline on a spiro[4.5]decane scaffold, has been achieved by utilizing an enantiomerically pure alcohol as the starting material.
Kazuhiro Takenaka, Toyohiro Nagano, Shinobu Takizawa, Hiroaki Sasai   +3 more
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2‐Isoxazoline derivatives. Part I. A base‐promoted fragmentation of 2‐isoxazolines

Journal of Heterocyclic Chemistry, 1968
AbstractThe action of bases on 3‐aryl (or alkyl)‐5‐acyl‐2‐isoxazolines has been shown to give rise to the corresponding aromatic (or aliphatic) nitriles and α‐diketones by cleavage of the O‐N and C3C4 bonds of the heterocyclic ring. This fragmentation reaction has been extended to other 2‐isoxazolines substituted in the 5‐position with electron ...
Giorgio Bianchi, Remo Gandolfi, Paolo Grünanger   +2 more
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Structure of a substituted isoxazoline

Acta Crystallographica Section C Crystal Structure Communications, 1987
L'oxyde de cyano-3 tetramethyl-4,4,5,5 dihydro-4,5 isoxazole, C 8 H 12 N 2 O 2 , cristallise dans le systeme orthorhombique, groupe Pna2 1 et sa structure est affinee jusqu'a R=0,065.
C. George, R. Gilardi
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Unusual transformations of 2-isoxazolines

Russian Chemical Reviews, 1997
The data on unusual transformations of 2-isoxazolines observed in both their preparation by traditional methods and various reactions, mostly with nucleophilic reagents, are considered systematically. Possible mechanisms of these reactions are discussed.
Elena V Koroleva, Fedor A Lakhvich
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