Three atoms insertion and addition reactions of α-diazo-β-ketoesters catalyzed by CpRu-complexes

Abstract

The goal of this PhD was to explore the reactivity of acceptor/acceptor ruthenium metal carbenes toward several Lewis basic functional groups such as carbonyl-containing moieties and cyclic ethers. In fact, α-diazo-β-ketoesters and combinations of cationic [CpRu(CH3CN)3]+ complexes and diimine ligands selectively provided different classes of oxygen containing heterocycles in single step processes. In particular, a new reactivity was discovered in the presence of tetrahydrofuran moieties leading to original enol-acetal products through unexpected 1,3-C-H insertion reactions. Also, in a new development that uses epoxides as substrates, acceptor/acceptor ruthenium metal carbenes underwent three-atom insertions, rather than lead to the usual deoxygenation pathway. Original 1,4-dioxene motifs were obtained as single regio- and stereoisomers. A perfect syn stereochemistry was observed for the ring opening, which behaves as an SN1-like transformation otherwise.