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Frank Rominger - One of the best experts on this subject based on the ideXlab platform.
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transannular reactions of two non parallel 1 3 butadiyne units syntheses structures and protonation reactions of 1 isopropyl 1 azacyclopentadeca 3 5 11 13 Tetrayne and 1 isopropyl 1 azacyclohexadeca 3 5 12 14 Tetrayne
European Journal of Organic Chemistry, 2004Co-Authors: Erik M Schmidt, Rolf Gleiter, Frank RomingerAbstract:The syntheses of 1-isopropyl-1-azacyclopentadeca-3,5,11,13-Tetrayne (15a) and 1-isopropyl-1-azacyclohexadeca-3,5,12,14-Tetrayne (15b) were accomplished in a stepwise approach. The key intermediates were 1,14-dibromotetradeca-2,4,10,12-Tetrayne (14a) and 1,15-dibromopentadeca-2,4,11,13-Tetrayne (14b). The ring closure to 15a and 15b was achieved by reaction with isopropylamine. X-ray investigations on single crystals of 15a and 15b revealed a non-parallel orientation of the 1,3-butadiyne units. The reaction of 15b with concd. HCl in ethanol yielded 5,12-dichloro-2-isopropyl-1,2,3,6,7,8,9,10-octahydrocyclonona[e]isoindole (16c) and 5-chloro-2-isopropyl-2,3,6,7,8,9,10,11-octahydrocyclonona[e]isoindol-12(1H)-one (17c). A mechanism for the reaction of 15b with HCl is proposed. The reaction of 15a with concd. HCl in ethanol gives 5-chloro-2-isopropyl-2,3,7,8,9,10-hexahydrocycloocta[e]isoindol-11(6H)-one (24c). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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transannular reactions of two parallel 1 3 butadiynes syntheses structures and reactions of 1azacyclotetradeca 3 5 10 12 Tetrayne derivatives
Chemistry: A European Journal, 2003Co-Authors: Erik M Schmidt, Rolf Gleiter, Frank RomingerAbstract:The synthesis of 1-alkyl and 1-aryl-1-azacyclotetradeca-3,5,10,12-Tetraynes was achieved in a stepwise approach. The key intermediate was 1,13-dibromotrideca-2,4,9,11-Tetrayne (18). Reaction with methyl- (19 a), ethyl- (19 b), isopropyl- (19 c), n-butyl- (19 d), and tert-butylamine (19 e) as well as aniline (19 f) and p-methoxyaniline (19 g) gave the corresponding 14-membered Tetraynes 20 a-20 g. The ring inversion process of 20 b was studied by variable temperature (1)H NMR spectroscopy. From these measurements a value of 10.6 kcal mol(-1) was calculated for DeltaG(not equal). X-ray investigations on single crystals of 20 b, 20 c, and 20 f revealed the axial position for the substituent at each nitrogen atom. For 20 b we encountered the chair conformation, for 20 c both chair and boat conformations, and for 20 f the boat conformation in the solid state. The reaction of 20 c with concentrated HCl in ethanol yielded 2,10-dichloro-6-isopropyl-6-azatricyclo[9.3.0.0(4,8)]tetradeca-1(11),2,4(8),9-tetraene (25 c). Compound 25 c was oxidized by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) to 27 c. The structure of the latter was confirmed by X-ray investigations. The reaction of 20 c in aqueous HCl lead to the formation of 10-chloro-2-isopropyl-1,3,4,6,7,8-hexahydro-2H-benzo[g]isoquinolin-9-one (37 c). The structure of 37 c was verified by X-ray studies on single crystals.
Rolf Gleiter - One of the best experts on this subject based on the ideXlab platform.
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transannular ring closure of a 1 8 diazacyclotetradeca 3 5 10 12 Tetrayne to a tricyclic system with a central cyclooctatetraene ring
European Journal of Organic Chemistry, 2009Co-Authors: Rolf Gleiter, Kirstin Hovermann, Birgit Esser, Arkasish BandyopadhyayAbstract:The addition of two equivalents of hydrochloric acid to N,N′-diisopropyl-1,8-diazacyclotetradeca-3,5,10,12-Tetrayne (13) afforded a tricyclic scaffold in which a central dichloro-substituted cyclooctatetraene ring is annelated by two N-isopropyl-2,5-dihydropyrrole rings (14). Three other minor products were congeners of 14 in which one (15, 16) or both (17) of the 2,5-dihydropyrrole rings are oxidized. In 16 the chlorine atoms adopt different positions.The assignment of the structures of 14–17 is based on the result of an X-ray investigation on single crystals of 16 and NMR studies. The structural assignments of 14 and 15 were corroborated by labeling experiments with DCl. The regiochemistry in the addition of the second equivalent of hydrochloric acid to 13 was illuminated by DFT calculations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
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transannular reactions of two non parallel 1 3 butadiyne units syntheses structures and protonation reactions of 1 isopropyl 1 azacyclopentadeca 3 5 11 13 Tetrayne and 1 isopropyl 1 azacyclohexadeca 3 5 12 14 Tetrayne
European Journal of Organic Chemistry, 2004Co-Authors: Erik M Schmidt, Rolf Gleiter, Frank RomingerAbstract:The syntheses of 1-isopropyl-1-azacyclopentadeca-3,5,11,13-Tetrayne (15a) and 1-isopropyl-1-azacyclohexadeca-3,5,12,14-Tetrayne (15b) were accomplished in a stepwise approach. The key intermediates were 1,14-dibromotetradeca-2,4,10,12-Tetrayne (14a) and 1,15-dibromopentadeca-2,4,11,13-Tetrayne (14b). The ring closure to 15a and 15b was achieved by reaction with isopropylamine. X-ray investigations on single crystals of 15a and 15b revealed a non-parallel orientation of the 1,3-butadiyne units. The reaction of 15b with concd. HCl in ethanol yielded 5,12-dichloro-2-isopropyl-1,2,3,6,7,8,9,10-octahydrocyclonona[e]isoindole (16c) and 5-chloro-2-isopropyl-2,3,6,7,8,9,10,11-octahydrocyclonona[e]isoindol-12(1H)-one (17c). A mechanism for the reaction of 15b with HCl is proposed. The reaction of 15a with concd. HCl in ethanol gives 5-chloro-2-isopropyl-2,3,7,8,9,10-hexahydrocycloocta[e]isoindol-11(6H)-one (24c). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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transannular reactions of two parallel 1 3 butadiynes syntheses structures and reactions of 1azacyclotetradeca 3 5 10 12 Tetrayne derivatives
Chemistry: A European Journal, 2003Co-Authors: Erik M Schmidt, Rolf Gleiter, Frank RomingerAbstract:The synthesis of 1-alkyl and 1-aryl-1-azacyclotetradeca-3,5,10,12-Tetraynes was achieved in a stepwise approach. The key intermediate was 1,13-dibromotrideca-2,4,9,11-Tetrayne (18). Reaction with methyl- (19 a), ethyl- (19 b), isopropyl- (19 c), n-butyl- (19 d), and tert-butylamine (19 e) as well as aniline (19 f) and p-methoxyaniline (19 g) gave the corresponding 14-membered Tetraynes 20 a-20 g. The ring inversion process of 20 b was studied by variable temperature (1)H NMR spectroscopy. From these measurements a value of 10.6 kcal mol(-1) was calculated for DeltaG(not equal). X-ray investigations on single crystals of 20 b, 20 c, and 20 f revealed the axial position for the substituent at each nitrogen atom. For 20 b we encountered the chair conformation, for 20 c both chair and boat conformations, and for 20 f the boat conformation in the solid state. The reaction of 20 c with concentrated HCl in ethanol yielded 2,10-dichloro-6-isopropyl-6-azatricyclo[9.3.0.0(4,8)]tetradeca-1(11),2,4(8),9-tetraene (25 c). Compound 25 c was oxidized by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) to 27 c. The structure of the latter was confirmed by X-ray investigations. The reaction of 20 c in aqueous HCl lead to the formation of 10-chloro-2-isopropyl-1,3,4,6,7,8-hexahydro-2H-benzo[g]isoquinolin-9-one (37 c). The structure of 37 c was verified by X-ray studies on single crystals.
Yoshinori Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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synthesis of new donor acceptor donor materials via au catalyzed double cascade cyclization
ChemInform, 2012Co-Authors: Giovanni Ferrara, Tienan Jin, Kazuaki Oniwa, Jian Zhao, Abdullah M Asiri, Yoshinori YamamotoAbstract:Double cascade cyclization of arenyl Tetraynes gives benzothiadiazole derivatives and related compounds.
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synthesis of new donor acceptor donor materials via au catalyzed double cascade cyclization
Tetrahedron Letters, 2012Co-Authors: Giovanni Ferrara, Tienan Jin, Kazuaki Oniwa, Jian Zhao, Abdullah M Asiri, Yoshinori YamamotoAbstract:Abstract A new class of symmetric π-conjugated donor–acceptor–donor (D–A–D) materials, with aryl- or heteroaryl[a]annulated carbazole (AHA[a]C) moieties as the donors and with 2,1,3-benzothiadiazole (BT) as an acceptor, has been synthesized via NaAuCl4-catalyzed double cascade cyclization of arenyl Tetraynes in ethanol in good to high yields. Photophysical and electrochemical properties of the new D–A–D materials were investigated.
Erik M Schmidt - One of the best experts on this subject based on the ideXlab platform.
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transannular reactions of two non parallel 1 3 butadiyne units syntheses structures and protonation reactions of 1 isopropyl 1 azacyclopentadeca 3 5 11 13 Tetrayne and 1 isopropyl 1 azacyclohexadeca 3 5 12 14 Tetrayne
European Journal of Organic Chemistry, 2004Co-Authors: Erik M Schmidt, Rolf Gleiter, Frank RomingerAbstract:The syntheses of 1-isopropyl-1-azacyclopentadeca-3,5,11,13-Tetrayne (15a) and 1-isopropyl-1-azacyclohexadeca-3,5,12,14-Tetrayne (15b) were accomplished in a stepwise approach. The key intermediates were 1,14-dibromotetradeca-2,4,10,12-Tetrayne (14a) and 1,15-dibromopentadeca-2,4,11,13-Tetrayne (14b). The ring closure to 15a and 15b was achieved by reaction with isopropylamine. X-ray investigations on single crystals of 15a and 15b revealed a non-parallel orientation of the 1,3-butadiyne units. The reaction of 15b with concd. HCl in ethanol yielded 5,12-dichloro-2-isopropyl-1,2,3,6,7,8,9,10-octahydrocyclonona[e]isoindole (16c) and 5-chloro-2-isopropyl-2,3,6,7,8,9,10,11-octahydrocyclonona[e]isoindol-12(1H)-one (17c). A mechanism for the reaction of 15b with HCl is proposed. The reaction of 15a with concd. HCl in ethanol gives 5-chloro-2-isopropyl-2,3,7,8,9,10-hexahydrocycloocta[e]isoindol-11(6H)-one (24c). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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transannular reactions of two parallel 1 3 butadiynes syntheses structures and reactions of 1azacyclotetradeca 3 5 10 12 Tetrayne derivatives
Chemistry: A European Journal, 2003Co-Authors: Erik M Schmidt, Rolf Gleiter, Frank RomingerAbstract:The synthesis of 1-alkyl and 1-aryl-1-azacyclotetradeca-3,5,10,12-Tetraynes was achieved in a stepwise approach. The key intermediate was 1,13-dibromotrideca-2,4,9,11-Tetrayne (18). Reaction with methyl- (19 a), ethyl- (19 b), isopropyl- (19 c), n-butyl- (19 d), and tert-butylamine (19 e) as well as aniline (19 f) and p-methoxyaniline (19 g) gave the corresponding 14-membered Tetraynes 20 a-20 g. The ring inversion process of 20 b was studied by variable temperature (1)H NMR spectroscopy. From these measurements a value of 10.6 kcal mol(-1) was calculated for DeltaG(not equal). X-ray investigations on single crystals of 20 b, 20 c, and 20 f revealed the axial position for the substituent at each nitrogen atom. For 20 b we encountered the chair conformation, for 20 c both chair and boat conformations, and for 20 f the boat conformation in the solid state. The reaction of 20 c with concentrated HCl in ethanol yielded 2,10-dichloro-6-isopropyl-6-azatricyclo[9.3.0.0(4,8)]tetradeca-1(11),2,4(8),9-tetraene (25 c). Compound 25 c was oxidized by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) to 27 c. The structure of the latter was confirmed by X-ray investigations. The reaction of 20 c in aqueous HCl lead to the formation of 10-chloro-2-isopropyl-1,3,4,6,7,8-hexahydro-2H-benzo[g]isoquinolin-9-one (37 c). The structure of 37 c was verified by X-ray studies on single crystals.
I Ueda - One of the best experts on this subject based on the ideXlab platform.
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effect of water molecules on the cycloaromatization of non conjugated aromatic Tetraynes
Bulletin of the Chemical Society of Japan, 2006Co-Authors: Hiroki Inai, Kazuhiro Miyawaki, I UedaAbstract:Cycloaromatization of the thienyl Tetrayne 1, which was prepared in several steps from bis(trimethylsilyl)butadiyne and 3-bromothiophene-2-carbaldehyde, in benzene (0.33 mM) in the presence of molecular sieves 3A at room temperature gave the indeno[2,1-b]thiophene ring-fused 1H-2-benzopyran derivative 10 and indeno[2,1-b]thiophene derivative 11 in 11 and 40% yields, respectively. In contrast, cycloaromatization of 1 in the presence of water molecules at room temperature gave the indeno[2,1-b]thiophene ring-fused 1H-2-benzopyran derivative 10 and the indene ring-fused indeno[2,1-b]thiophene derivative 12 in 82 and 14% yields, respectively. Cycloaromatization of the phenyl Tetrayne 9 in the presence of water molecules at room temperature also resulted in a dramatic change in product yields.
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synthesis and inclusion properties of 6 6 bi benzo b fluoren 5 ol derivative by cycloaromatization
Chemistry Letters, 2006Co-Authors: Masako Suehiro, I UedaAbstract:Aromatic non-conjugated Tetraynes underwent step-by-step cycloaromatization to yield 6,6'-bi(benzo[b]fluoren-5-ol) derivative 1 via benzo[b]fluoren-5-ol derivatives. Treatment of compound 1 with a kind of organic guest compounds afforded crystalline inclusion compounds (clathrates).
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cycloaromatization of a non conjugated polyenyne system synthesis of 5h benzo d fluoreno 3 2 b pyrans via diradicals generated from 1 2 4 2 alkoxymethylphenyl butan 1 3 diynyl phenylpentan 2 4 diyn 1 ols and trapping evidence for the 1 2 didehydroben
Tetrahedron Letters, 1997Co-Authors: Kazuhiro Miyawaki, Riho Suzuki, Tomikazu Kawano, I UedaAbstract:Non-conjugated Tetraynes 1 undergo thermal intramolecular cyclization to non-benzenoid diradicals (23) followed by radical cycloaromatization at 25 °C to provide 7-dehydro-5H-benzo[d]fluoreno[3,2-b]pyran monoradical (24) and alkyl radicals (25). Hydrogen abstraction of 24 gives 5H-benzo[d]fluoreno[3,2-b]pyrans (3) which are converted to 4 by reaction with 25. On the other hand, 2 gives 5H-fluorenol (5), indicating the formation of 1,2-didehydrobenzene diradical intermediates (28 and 29). These radicals are trapped as the corresponding Diels-Alder-type products by reaction with an aromatic diene, anthracene.