Catalyst for Efficient Cleavage of Allyloxy Bonds

Nagoya, Japan 2014 Tetrahedron Prize for Creativity in Organic Chemistry, Palladium and Other Transition Metal-Catalyzed Reactions: Invention and Applications Soft ruthenium and hard Brønsted acid combined catalyst for efficient cleavage of allyloxy bonds. Application to protecting group chemistry with Chemspeed’s Fully Automated SYNTHESIZER “We show that a monocationic CpRu(II) complex of quinaldic acid (QAH) and a monocationic CpRu(IV)(p-allyl)QA complex catalyze efficient cleavage of the allyloxy bond in allyl ethers, allyl esters, allyl carbonates, and allyl carbamates in methanol without the need for additional nucleophiles. The only co-product is volatile allyl methyl ether, enhancing operational simplicity during isolation of the de-protected alcohols, acids, and amines. This clean and high-performance catalytic system should contribute to protecting group chemistry during the multistep synthesis of pharmaceutically important natural products. Full details of this system, including the mechanism, are reported.” For details: Soft ruthenium and hard Brønsted acid combined catalyst for efficient cleavage of allyloxy bonds. Application to protecting group chemistry Shinji Tanaka, Yusuke Suzuki, Hajime Saburi, Masato Kitamura Nagoya University, Graduate School of Pharmaceutical Sciences, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan Tetrahedron, Volume 71, Issue 37, 16 September 2015, Pages 6559–6568 DOI:10.1016/j.tet.2015.04.088