Results 91 to 100 of about 400 (141)

Conformations of cyclobutane

Tetrahedron, 1974
Abstract The literature concerning the structures of compounds containing saturated, 4-carbon rings is reviewed critically, and the variety of conformations (dihedral angles of 0° to 30° ± 6°) of the cyclobutane ring are tabulated and discussed.
F.Albert Cotton, Bertram A. Frenz
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Rearrangements of Cyclobutanes

ChemInform, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
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Detailed Dynamics of the Photodissociation of Cyclobutane

The Journal of Physical Chemistry A, 2007
Semiclassical electron-radiation-ion dynamics simulations are reported for the photodissociation of cyclobutane into two molecules of ethylene. The results clearly show the formation of the tetramethylene intermediate diradical, with dissociation completed in approximately 400 fs.
Yusheng, Dou, Yibo, Lei, Anyang, Li, Zhenyi, Wen, Ben R, Torralva, Glenn V, Lo, Roland E, Allen   +6 more
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Cyclobutanes from Combretum albopunctatum

Phytochemistry, 2004
A dichloromethane extract of the aerial parts of Combretum albopunctatum Suesseng afforded five phenolic compounds-three known flavonoids and two novel cyclobutane chalcone dimers. The chemical structures were determined by standard spectroscopic techniques and the structure and relative stereochemistry of one chalcone dimer, rel-(1 alpha,2 beta)-di-(2,
Katerere, D.R., Gray, A.I., Kennedy, A.R., Nash, R.J., Waigh, R.D.   +4 more
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The Preparation of Methylene Cyclobutane and Methyl Δ' Cyclobutane

1941
No abstract.
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Synthesis of Cyclobutanes

ChemInform, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
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A Cyclobutane possessing Hypotensive Activity

Nature, 1964
A NUMBER of non-quaternary bases have been found to possess ganglionic blocking and hypotensive properties1–5. In investigating the pharmacological properties of a new series of cyclobutanes6, one of them, 3-dimethylamino-2,2,4,4-tetramethyl-cyclobutanol, was found to exhibit a lowering activity of the blood pressure of long duration.
A W, PIRCIO, A, WILSON, S, KUNA, R H, HASEK, J C, MARTIN   +4 more
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A Novel Strategy for Cyclobutane Formation. Fine Tuning of Cyclobutanation vs Cyclopropanation

The Journal of Organic Chemistry, 1998
The reactions of (E)-1-(phenylseleno)-2-(trimethylsilyl)ethene (1a) and (E)-1-(phenylseleno)-2-(triethylsilyl)ethene (1b) with dimethyl 1,1-dicyanoethene-2,2-dicarboxylate (2) in the presence of SnCl4 in CH2Cl2 at −78 °C for 1 h exclusively afforded [2 + 2] cycloadducts 3a and 3b in 71% and 78% yields, respectively. The exclusive [2 + 2] selectivity in
Shoko Yamazaki, Hitoshi Kumagai, Shinichi Yamabe, Kagetoshi Yamamoto   +3 more
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Investigations in the cyclobutane series

Journal of Organometallic Chemistry, 1977
Abstract Acetylation of cyclobutadieneiron tricarbonyl gives the mono and the diacetyl derivative. Some reactions of the latter, including that with hydrazine to give a pyridazinocyclobutadiene complex, are described.
Ilie G. Dinulescu, Emil G. Georgescu, Margareta Avram   +2 more
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Carbon‐13 NMR spectra of methylated cyclobutanes and ethyl cyclobutane‐carboxylates

Organic Magnetic Resonance, 1980
AbstractThe 13C NMR spectra of cyclobutane and seven methylated homologs and of ethyl cyclobutanecarboxylate and five isomeric diethyl cyclobutanedicarboxylates are reported and substituent parameters for methyl groups in methylcyclobutanes are calculated. Of note is a sizeable and nearly configuration‐independent upfield shifting γ‐effect.
Ernest L. Eliel, K. Michal Pietrusiewicz
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