Cyclization Of Silyl Enol Ethers Research Articles

Construction of Methylenecycloheptane Frameworks through 7-Exo-Dig Cyclization of Acetylenic Silyl Enol Ethers Catalyzed by Triethynylphosphine−Gold Complex

A cationic gold(I) complex bearing a semihollow-shaped triethynylphosphine ligand efficiently catalyzed the 7-exo-dig cyclization of silyl enol ethers with an ω-alkynic substituent. The reaction gave various methylenecycloheptane derivatives with an exo- or endocyclic carbonyl group. The protocol was applicable not only to cyclic substrates that form bicyclic frameworks but also to acyclic ones with or without substituents in a carbon chain tether.

ChemInform Abstract: Rhenium(I)‐Catalyzed Cyclization of Silyl Enol Ethers Containing a Propargyl Carboxylate Moiety: Versatile Access to Highly Substituted Phenols.

AbstractDepending on the structure of the silyl enol ether moiety, either nucleophilic addition of the silyl enol ether moiety, or 1,2‐acyloxy migration occurs to give two kinds of substituted phenols.

Synthesis of Novel Steroid Backbones via Photoinduced Electron Transfer Initiated Domino Cyclizations of Silyl Enol Ethers

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis of Novel Steroid Backbones via Photoinduced Electron Transfer Initiated Domino Cyclizations of Silyl Enol Ethers

Photoinduced electron transfer was used to activate silyl enol ethers. The generated radical cations of specifically designed precursors undergo ring closure reactions to yield novel steroid compounds. These domino reactions proceed with high stereo-selectivity. The synthesis of the complex silyl enol ethers, the stereo-selective domino cyclization process and the assignment of stereochemistry of the novel steroid compounds is presented.

Synthesis and PET Oxidative Cyclization of Silyl Enol Ethers: Build‐up of Quasi‐Steroidal Carbocycles.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis and PET oxidative cyclization of silyl enol ethers: build-up of quasi-steroidal carbocycles

PET oxidative cyclization of silyl enol ethers carrying suitable side chains with olefinic double bonds results in the stereoselective formation of carbocycles. Two model compounds for investigating the influence of silyl enol ether ring size are synthesized. Furthermore the synthesis of a quasi-steroidal carbocycle with an unnatural configuration is presented.