176435-52-2Relevant academic research and scientific papers
Olefin-Supported Cationic Copper Catalysts for Photochemical Synthesis of Structurally Complex Cyclobutanes
Gravatt, Christopher S.,Melecio-Zambrano, Luis,Yoon, Tehshik P.
, p. 3989 - 3993 (2021)
The sole method available for the photocycloaddition of unconjugated aliphatic alkenes is the Cu-catalyzed Salomon–Kochi reaction. The [Cu(OTf)]2?benzene catalyst that has been standard in this reaction for many decades, however, is air-sensitive, prone to photodecomposition, and poorly reactive towards sterically bulky alkene substrates. Using bench-stable precursors, an improved catalyst system with superior reactivity and photostability has been designed, and it offers significantly expanded substrate scope. The utility of this new catalyst for the preparation of sterically crowded cyclobutane structures is highlighted through the preparation of the cores of the natural products sulcatine G and perforatol.
Development of a method for the reductive cyclization of enones by a titanium catalyst
Kablaoui, Natasha M.,Buchwald, Stephen L.
, p. 3182 - 3191 (2007/10/03)
An effective protocol in which bis(trimethylphosphine)titanocene is used to catalyze the reductive cyclization of enones to cyclopentanols via a metallacyclic intermediate has been developed. The key step in the process is the cleavage of the titanium-oxygen bond in the metallacycle by a silane to regenerate the catalyst. Mechanistic aspects of the reaction are discussed and the diastereoselectivity of the transformation is studied using both achiral and chiral substrates. The scope and limitations of the procedure are described. An in situ protocol for the generation of the air- and moisture-sensitive catalyst has also been developed. This work demonstrates, for the first time, the viability of using an early transition metal complex to catalyze the reductive cyclization of an alkene with a heteroatom-containing functional group.An effective protocol in which bis(trimethylphosphine) titanocene is used to catalyze the reductive cyclization of enones to cyclopentanols via a metallacyclic intermediate has been developed. The key step in the process is the cleavage of the titanium-oxygen bond in the metallacycle by a silane to regenerate the catalyst. Mechanistic aspects of the reaction are discussed and the diastereoselectivity of the transformation is studied using both achiral and chiral substrates. The scope and limitations of the procedure are described. An in situ protocol for the generation of the air-and moisture-sensitive catalyst has also been developed. This work demonstrates, for the first time, the viability of using an early transition metal complex to catalyze the reductive cyclization of an alkene with a heteroatom containing functional group.
