5701-83-7Relevant articles and documents
1,3-Chlorine Shift to a Vinyl Cation: A Combined Experimental and Theoretical Investigation of the E-Selective Gold(I)-Catalyzed Dimerization of Chloroacetylenes
Kreuzahler, Mathis,Daniels, Alyssa,W?lper, Christoph,Haberhauer, Gebhard
, p. 1337 - 1348 (2019)
Metal-catalyzed dimerization reactions of terminal acetylenes are well known in the literature. However, only a few examples of the dimerization of halogen-substituted acetylenes are described. The products of the latter metal-catalyzed dimerization are the branched head-to-tail enynes. The formation of the corresponding linear head-to-head enynes has not been reported yet. Herein, we demonstrate by means of quantum chemical methods and experiments that the head-to-head dimerization of chloroarylacetylenes can be achieved via mono gold catalysis. Under the optimized conditions, a clean and complete conversion of the starting materials is observed and the dimeric products are obtained up to 75% NMR yield. A mechanistic investigation of the dimerization reaction reveals that the branched head-to-tail vinyl cation is energetically more stable than the corresponding linear head-to-head cation. However, the latter can rearrange by an unusual 1,3-chlorine shift, resulting in the highly stereoselective formation of the trans product, which corresponds to the gold complex of the head-to-head E-enyne. The activation barrier for this rearrangement is extremely low (ca. 2 kcal/mol). As the mono gold-catalyzed dimerization can be conducted in a preparative scale, this simple synthesis of trans-1,2-dichloroenynes makes the gold(I)-catalyzed head-to-head dimerization of chloroarylacetylenes an attractive method en route to more complex conjugated enyne systems and their congeners.
Nickel-catalyzed anti-Markovnikov hydroarylation of alkenes
Nguyen, Julia,Chong, Andrea,Lalic, Gojko
, p. 3231 - 3236 (2019/03/21)
We have developed a nickel-catalyzed hydroarylation of alkenes using aryl halides as coupling partners. Excellent anti-Markovnikov selectivity is achieved with aryl-substituted alkenes and enol ethers. We also show that hydroarylation occurs with alkyl substituted alkenes to yield linear products. Preliminary examination of the reaction mechanism suggests irreversible hydrometallation as the selectivity determining step of the hydroarylation.
Synthesis and PGE2 inhibitory activity of novel diarylheptanoids
McLane, Richard D.,Le Cozannet-Laidin, Léon,Boyle, Maxwell S.,Lanzillotta, Lindsey,Taylor, Zachary L.,Anthony, Sarah R.,Tranter, Michael,Onorato, Amber J.
supporting information, p. 334 - 338 (2018/02/15)
Prostaglandin E2 (PGE2) is a lipid mediator of inflammation and its inhibition has become a popular drug target due to its harmful physiological roles. Diarylheptanoids are one class of compounds that have shown successful inhibition of PGE2. This paper reports the synthesis and PGE2 inhibitory activity of a series of analogues of a naturally occurring diarylheptanoid. The most efficacious compounds were examined for dose-dependent PGE2 inhibition. Among several promising compounds, the lead candidate exhibited an IC50 value of 0.56 ng/μL or 1.7 μM with no detectable toxicity at the highest dose of 10 ng/μL.
