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ChemInform Abstract: Cyclic Ketones in Spiroannulation.
ChemInform, 2009AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Vidar Bjoernstad, Kjell Undheim
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.alpha.-Substitution-spiroannulation of saturated ketones
Journal of the American Chemical Society, 1983α-Substitution-spiroannelation de la cyclopentanone.
Barry M. Trost, Michael K. T. Mao
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Spiroannulation approach to pentalenene, an angular triquinane sesquiterpene
The Journal of Organic Chemistry, 1994The route to the angular triquinane (±)-pentalenene (1a) followed from an efficient geminal acylation of the acetal of isophorone or its homolog 6b by 1,2-bis((trimethylsilyl)oxy)cyclobutene (3) in the presence of boron trifluoride etherate. Ring cleavage and reclosure (9→11) secured the required spiro[4.4] nonane system with a pendant ketone function ...
Y.-J. Wu, Y.-Y. Zhu, D. Jean Burnell
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Gold(I)-Catalyzed Ring-Expanding Spiroannulation of Cyclopropenones with Enynes
The Journal of Organic Chemistry, 2014The gold(I)-catalyzed ring-expanding spiroannulation of cyclopropenones with enynes is reported here. A molecule of water is incorporated into the products during the spiroannulation to afford spirocyclic cyclopentenones containing an alcohol functionality.
Takanori, Matsuda, Yusuke, Sakurai
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Synthesis of spiroannulated oligopyrrole macrocycles derived from lithocholic acid
Steroids, 2009Two new steroidal spiroannulated calix[4]pyrroles 5 and 10, derived from bile acids (lithocholate), were prepared by the acid catalyzed condensation of methyl-3,3-bis(pyrrol-2-yl)-5beta-cholan-24-oate 3 with carbonyl compounds and with 2,2'-propane-2,2-diylbis(1H-pyrrole), respectively.
Thi Thu Huong N +4 more
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ChemInform Abstract: An Efficient Asymmetric Spiroannulation Process.
ChemInform, 1990AbstractThe keto ester (I) reacts with the chiral amine (R)‐(II) to give a mixture of diastereomers (III) which undergoes asymmetric spiroannulation, forming stereoselectively the imine (IV).
J. D'ANGELO +3 more
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Acid-Catalyzed [4+1]-Dearomatization Spiroannulation of Hydroquinones and Naphthols
Synlett, 2023AbstractAcid-catalyzed [4+1]-dearomatization spiroannulation reactions of electron-rich hydroquinone and naphthol derivatives were demonstrated as convenient methods to access spirocyclic cyclohexadienone derivatives. The Lewis acid Bi(OTf)3 exhibited the best catalytic performance when a 1,2-dialkynylbenzene was used as the electrophile for the ...
Zhi Li, Nan Ding
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Enantioselective Synthesis of Ring-Fused Spiroannulated 1,2,3-Thiadiazole Derivatives
The Journal of Organic Chemistry, 2016An organocatalytic enantioselective domino α-amination/oxidative coupling/cyclization of thioamides to azodicarboxylates catalyzed by an easily available organic catalyst has been developed. The key step, oxidative coupling, is smoothly fulfilled in air.
Xue-Mei, Zeng, Jian-Wu, Xie
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Studies Directed to the Synthesis of New C‐5 Spiroannulated Julolidines.
ChemInform, 2002AbstractFor Abstract see ChemInform Abstract in Full Text.
Alirio Palma +6 more
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ChemInform Abstract: CYCLOCONTRACTION ‐ SPIROANNULATION: A STEREOSELECTIVE APPROACH TO SPIROCYCLES
Chemischer Informationsdienst, 1983AbstractDie Umsetzung der Ketosulfone (I) mit der Al‐Spezies (II) führt durch Cyclisierung [‐ (III)] und Ringkontraktion/Isomerisierung zu den Spirocyclen (V).
B. M. TROST, B. R. ADAMS
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