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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Zeitaufgelöste und kryogene Untersuchungen von Carbonylradikalen und Nitrenen

Schade, Olaf. January 2001 (has links) (PDF)
Bochum, Universiẗat, Diss., 2001.
12

Copper(II) Complexes for Olefin Aziridination and Cyclopropanation: Towards Asymmetric N- and C- Transfer Catalyst

Valle, Henry U 14 December 2018 (has links)
Aziridines and cyclopropanes are valued as important building blocks for the synthesis of a wide range of organic compounds, including biologically active compounds and pharmaceuticals. The development for more efficient and cost-effective catalysts for the atom transfer reaction with olefins is a continuing area of research in both organic and inorganic chemistry. Transition metal complexes, which catalyze reactions of olefins with nitrenes and carbenes, are well-developed efficient, approaches to the direct synthesis of aziridines and cyclopropanes, but traditionally rely on expensive synthetic methods. As part of our efforts in the catalytic formation of C—C and C—N bonds, herein we show the development of a new and efficient copper(II) catalysts that exhibits high reactivity forming cyclopropanes and aziridines from a range of olefins. These catalytic systems have also shown a propensity to conduct these atom-transfer reactions in aqueous solutions, affording the opportunity to use bio-macromolecules, like DNA, to induce enantioselectivity.
13

S-substituted thiophenes as compounds of agrochemical interest

Campbell, Stuart John January 1997 (has links)
No description available.
14

Copper-Catalyzed Amination of Indoles via C-H Bond Activation

Pan, Ming-kai 07 September 2012 (has links)
A new protocol for direct amination of N-Methyl-2-phenylindole catalyzed by copper(II) trifluoromethanesulfonate was presented. Both of (E)-N-(1,1'-Dimethyl-2,2' -diphenyl-2,3'-biindolin-3-ylidene)-4-methylbenzenesulfonamide¡]4¡^and 4-methyl -N-(1-methyl-2-phenyl-1H-indol-3-yl)benzenesulfonamide¡]2¡^were obtained under the optimal reaction conditions (2.5 mol% Cu(OTf)2, 1.2 equiv PhI=O, 0.7 equiv PhI=NTs heated at 25 ¢J in acetonitrile for 1 hour) in 78 % and 11 % yields, respectively. In addition, (E)-N-(2-hydroxy-1-methyl-2-phenylindolin-3-ylidene)-4-methylbenzene sulfonamide ¡]6¡^and (E)-N-(1,1'-dimethyl-2,2'-diphenyl-2,3'-biindolin-3-ylidene) -4-methylbenzenesulfonamide ¡]4¡^were synthesized in 47 % and 24 % yields, respectively, by using 5 mol% Cu(OTf)2, 2 equiv PhI=O, 1.2 equiv PhI=NTs at ambient temperature in acetonitrile for 1 hour. Finally, 4-methyl-N-(1-methyl-2-oxo-3-phenyl indolin-3-yl)benzenesulfonamide ¡]3¡^and 1,1'-dimethyl-2,2'-diphenyl-2,3'-biindolin -3-one ¡]7¡^can be formed under the following reaction condition, 5 mol% Cu(OTf)2, 2 equiv PhI=O, 1.2 equiv PhI=NTs and 3 equiv Ag2CO3 heated at 100 ¢J in acetonitrile for 1 hour, in 41% and 22% yields, respectively.
15

Pyrolytic Study of 2-Azidocycloheptanone and 2-[2-(4-Methoxyphenyl)vinyl]benzofuran

Wu, Bo-Jian 18 June 2005 (has links)
Flash vacuum pyrolysis (FVP) of 2-azidocycloheptanone gave two products: 3,4,5,6-tetrahydro-1H-azocin-2-one and 1-hydroxy-2-oxo-4- azabicyclo[5.3.0]dec-4-ene-3-spiro-2¡¦-cycloheptanone. Flash vacuum pyrolysis of 2-[2-(4-methoxyphenyl)vinyl]benzofuran gave two products: 4-(2-benzofuran-2-ylvinyl)phenol and 1H-6-oxacyclopenta[c]fluorine.
16

Pyrolytic Study of 1-Azidoindene and 3-(4-Methoxystyryl)thiophene

Hsueh, Yu-tan 30 August 2005 (has links)
Flash vacuum pyrolysis (FVP) of 1-azidoindene, which via a nitrene intermediate, gave some products of rearrangement¡Gquinoline¡Bisoquinoline and 1-methylene-1H-isoindole¡CUnder pyrolytic conditions, 3-(4-methoxystyryl)thiophene could get a radical intermediate and gave 3-(4-hydroxystyryl)thiophene, or it gave contractive tricyclic compounds which having signals on spectrum but inseparable, like as indene structures.
17

1. Pyrolytic Study of Arylmethylazides 2. Pyrolytic Study of 2-Amino-3-methylpyridine and its Derivatives

Lee, Chin-Fan 27 June 2001 (has links)
Flash vacuum pyrolysis(FVP) of azidomethylthiophene,via a nitrene intermediate,gave two products,a dimer (thienylmethylidene-thienylamine) and a trimer (N,N`-dithienyl methylidene-thienylmethylidene diamine).The trimer underwent cyclization and dehydrogenation to afford 2,4,5-trithienylimidazole. However by the same route, FVP of azidomethylbenzo[b]furan produced only a trimer(dibenzo[b]furylmethylidene-N,N'-benzo[b]furylmethyl amine).
18

Pyrolytic Study of Benzoic 5-Benzyl-2-furoic Anhydride and 2-(2-Azidoethyl)thiophene

Shiue, Jiing-Chyuan 30 July 2001 (has links)
(1) The pyrolysis of benzoic 5-benzyl-2-furoic anhydride by using SS-FVP method can obtain the ring-opened product naphthalene, and no ring-contracted product and its further derivatives. (2) Flash vacuum pyrolysis (FVP) of 2-(2-azidoethyl)thiophene, via a nitrene intermediate gave 1,2-di(2-thienyl)ethane, 3,5-di(2-thienyl)pyridine, and 2-methylthiophene as the main products.
19

1. Pyrolytic Study of (5-Methyl-2-selenophenyl)methyl Benzoate 2. Pyrolytic Study of 2-Azidomethylselenophene

Chu, Chung-chen 27 June 2002 (has links)
(1) Flash vacuum pyrolysis (FVP) of (5-methyl-2-selenophenyl)methyl benzoate gave 4-methylene-4H-selenopyran. The structure was confirmed by trapping experiment. The mechanism for the 4-methylene-4H-selenopyran will be discussed. (2) Flash vacuum pyrolysis of 2-Azidomethylselenophene, via a nitrene intermediate, gave a trimer (N,N¡¦-di-2-selenophenylmethylidene-2-selenophenylmethylidene diamine).
20

Pyrolytic Study of 2-Azidoacetophenone and 2-Azido-1-(2-thienyl)ethanone

Lin, Tsung-Te 02 July 2002 (has links)
Flash vacuum pyrolysis (FVP) of 2-azidoacetophenone gave the dimer 2-benzoyl-4- phenylimidazole and the trimer: 2,3-dibenzoyl-5-phenylpyrazine. Flash vacuum pyrolysis of 2-azido-1-(2-thienyl)ethanone gave the dimer: 2-(2-fromylthienyl)-4-(2-thienyl)imidazole and 2-formylthiophene.

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