Construction of cyclic enones via gold-catalyzed oxygen transfer reactions

Abstract

SummaryDuring the last decade, gold-catalyzed reactions have become a tour de force in organic synthesis. Recently, the gold-, Brønsted acid- or Lewis acid-catalyzed oxygen transfer from carbonyl to carbon–carbon triple bond, the so-called alkyne–carbonyl metathesis, has attracted much attention because this atom economical transformation generates α,β-unsaturated carbonyl derivatives which are of great interest in synthetic organic chemistry. This mini-review focuses on the most recent achievements on gold-catalyzed oxygen transfer reactions of tethered alkynones, diynes or alkynyl epoxides to cyclic enones. The corresponding mechanisms for the transformations are also discussed.

Beyond olefins: new metathesis directions for synthesis

“…Subsequent electrocyclizations, which are proposed to proceed through an oxetenium intermediate, ultimately generate the carbonyl–alkyne metathesis product ( 75 ). 32–33…”

One‐Pot Synthesis of Naphtho[1′,2′:4,5]imidazo[1,2‐a]pyridin‐5‐yl(aryl)methanones through Sequential Sonogashira Coupling/Alkyne–Carbonyl Metathesis

“…Such reactions can enable the generation of huge libraries of scaffolds for high‐throughput screening, which is a key requisite in the drug discovery process. Alkyne‐carbonyl metathesis (ACM) represents a valuable tool for the synthesis of substituted α, β‐unsaturated carbonyl compounds by a [2+2] cycloaddition and cyclo‐reversion process between the C–O double bond and the C–C triple bond in an atom‐economical manner, which is a viable alternative to traditional aldol and Wittig reactions for the construction of C–C double bonds …”

Iron-Catalyzed Carbonyl–Alkyne and Carbonyl–Olefin Metathesis Reactions

“…The carbonyl-alkyne metathesis (oxygen transfer from carbonyl to carbon-carbon triple bond) is an atom-efficient reaction which had its rush time in the early 2000s as a gold-catalyzed reaction [23]. In contrast to stabilized Wittig reagents, the carbonyl-alkyne metathesis reaction offers a favorable alternative as it possesses full atom efficiency for the synthesis of highly functionalized alkene derivatives.…”