117299-03-3Relevant academic research and scientific papers
Diastereodivergent Reductive Cross Coupling of Alkynes through Tandem Catalysis: Z- and E-Selective Hydroarylation of Terminal Alkynes
Armstrong, Megan K.,Goodstein, Madison B.,Lalic, Gojko
, p. 10233 - 10241 (2018)
A diastereodivergent hydroarylation of terminal alkynes is accomplished using tandem catalysis. The hydroarylation allows highly selective synthesis of both E and Z diastereoisomers of aryl alkenes, from the same set of starting materials, using the same combination of palladium and copper catalysts. The selectivity is controlled by simple changes in the stoichiometry of the alcohol additive. The hydroarylation has excellent substrate scope and can be accomplished in the presence of various classes of compounds, including esters, nitriles, alkyl halides, epoxides, carbamates, acetals, ethers, silyl ethers, and thioethers. The Z-selective hydroarylation is accomplished using a new approach based on tandem Sonogashira coupling and catalytic semireduction. The E-selective hydroarylation involves an additional catalytic isomerization of the Z-alkene. Our explorations of the reaction mechanism explain the role of individual reaction components and how the subtle changes in the reaction conditions influence the rates of specific steps of the hydroarylation. Our studies also show that, although the Z- and E-selective hydroarylation reactions are mechanistically closely related, the roles of the palladium and copper catalysts in the two reactions are different.
Imidazolidinones as brain activators
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, (2008/06/13)
This invention relates to imidazolidinone compounds of the formula STR1 wherein Q is methylene group or a single bond: R is a heterocyclic group selected from the group consisting of pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl and 1,3-thiazolyl which may be unsubstituted or with a substituent selected from the group consisting of lower alkyl, lower alkoxy and halogen atom, wherein R is bonded to Q or, when Q is a single bond, to the imidazolidinone ring, through the carbon atom of R; the ring A is an unsubstituted phenyl or a substituted phenyl having 1 or 2 substituent(s) selected from the group consisting of lower alkyl, lower alkoxy, halogen, lower alkylthio, trihalogeno-lower alkyl and nitro; Y is vinylene group or ethynylene; m is a integer from 1 to 6 and n is 0, 1 or 2, or a pharmacetically acceptable salt thereof. These compounds aer useful as cerebral activators, anti-depressants and nootropic drugs.
