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Synthesis of tetrasubstituted alkenes via palladium-catalyzed domino-carbopalladation/C-H-activation
No full textA Fast Way to Fluorescence: A Fourfold Domino Reaction to Condensed Polycyclic Compounds
No full textA fast and efficient palladium-catalyzed fourfold domino Sonogashira/double-carbopalladation/C-H-activation reaction that converts simple aromatic systems into complex polycyclic hydrocarbons has been developed. A number of substituted products has thus been prepared in yields up to 89 %. The structural assignment has been confirmed by using single-crystal X-ray crystallography. The products show intriguing fluorescence activity and thus might serve as chemical sensors or fluorescent imaging dyes
ChemInform Abstract: A Fast Way to Fluorescence: A Fourfold Domino Reaction to Condensed Polycyclic Compounds.
No full textSynthesis of Tetrasubstituted Alkenes through a Palladium-Catalyzed Domino Carbopalladation/C-H-Activation Reaction
No full textHelical tetrasubstituted alkenes (7) were obtained in a highly efficient way through a palladium-catalyzed domino-carbopalladation/CH-activation reaction of propargylic alcohols 6 in good to excellent yields. Electron-withdrawing- and electron-donating substituents can be introduced onto the upper and lower aromatic rings. The substrates (6) for the domino process were synthesized by addition of the lithiated alkyne (20) to various aldehydes (19); moreover, the substrates were accessible enantioselectively (in 95?% ee) by reduction of the corresponding ketone using the Noyori procedure
Efficient Synthesis of Helical Tetrasubstituted Alkenes as Potential Molecular Switches: A Two-Component Palladium-Catalyzed Triple Domino Process
No full textPalladium-Catalyzed Domino Carbopalladation/C-H Activation for the Synthesis of Tetrasubstituted Alkenes Bearing Five- and Seven-Membered Rings
No full textA Pd-catalyzed domino carbopalladation/C-H-activation reaction of phenoxyphenyl-substituted propargylic alcohols was used for the synthesis of tetrasubstituted alkenes bearing either a dihydroindene or benzo[7] annulene motif. These compounds are of interest for the construction of molecular switches and motors
A facile synthesis of 3-substituted benzofurans and indoles through a palladiumcatalyzed domino carbopalladation/CH-activation/isomerization process
No full textNovel benzofurans 7 and indoles 8 have been prepared from 3 and 4 by a Pd-catalyzed mono-component three-fold domino carbopalladation/CH-activation/isomerization process and from 12 and 5 to give 8 by a two-component fourfold domino Sonogashira/carbopalladation/CH-activation/isomerization process
ChemInform Abstract: Palladium‐Catalyzed Domino Carbopalladation/C—H Activation for the Synthesis of Tetrasubstituted Alkenes Bearing Five‐ and Seven‐Membered Rings.
No full textSynthesis and Photochemical Investigations of Tetrasubstituted Alkenes as Molecular Switches-The Effect of Substituents
No full textMolecular switches based on helical tetrasubstituted alkenes, substituted with either electron-withdrawing (CF(3), F, CN; 2a-c, 3a, c) or -donating substituents (Me, OMe; 2d, e), have been synthesized from acyclic precursors 4 and 5 in a domino carbopalladation/Stille reaction. This palladium-catalyzed process allowed the rapid assembly of two C-C bonds, two six-membered rings, and the tetrasubstituted double bond in a completely diastereoselective fashion. The electronic effects of the substituents on the overall switching process were investigated by alternating irradiation of two different wavelength regions. Although the substituents had only a small influence on the absorption maxima, drastic differences in the switching behavior were observed
ChemInform Abstract: A Facile Synthesis of 3‐Substituted Benzofurans and Indoles Through a Palladium‐Catalyzed Domino Carbopalladation/CH‐Activation/Isomerization Process.
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