Oxidative Coupling of Terminal Alkyne with α-Hydroxy Ketone: An Expedient Approach toward Ynediones

Abstract

An efficient and mild copper-catalyzed one-pot approach toward ynediones has been established. A variety of ynediones were constructed directly through oxidative coupling of alkyne with α-hydroxy ketone. Oxygen-oxidizing and neutral conditions in one-pot for a wide range of substrates including natural product derivatives make this transformation highly efficient and practical. On the basis of control experiments, in situ IR measurements, and isotopic labeling experiments, a plausible mechanism involving intermediate phenylglyoxal was drawn. Applications by synthesis of various heterocycles were also investigated.

Three‐Component Activation/Alkynylation/Cyclocondensation (AACC) Synthesis of Enhanced Emission Solvatochromic 3‐Ethynylquinoxalines

“…Ynediones are densely functionalized polyelectrophilic functional groups with a powerful synthetic potential that has, however, scarcely been explored so far . As already mentioned, electron‐rich π‐nucleophiles can be successfully employed in the GACC sequence; however, no electron‐rich para ‐substituted arenes, carbazole and benzo[ b ]thiophene derivatives, and bromo‐substituted thiophenes could be successfully transformed (see Tables S1 and S2 in the Supporting Information).…”

Copper-catalyzed direct transformation of simple alkynes to alkenyl nitriles via aerobic oxidative N-incorporation

“… 13 Moreover, late-stage modification is a highly valuable strategy for medicinal chemistry research. 14 Therefore, several complex bioactive molecule derivatives were submitted to the optimal conditions ( Table 3 ). Natural alcohol derivatives containing ester or ether linkages, such as menthol, borneol, nopol and cholesterol, worked well in the current transformation, generating the corresponding alkenyl nitriles in 49–73% yield ( 4a , 4d–f ), respectively.…”

A General Strategy for Synthesis of Heterocyclic Hemiketal‐Containing α,β‐Unsaturated Ketones from Ynediones

“…Our group has always been working on developing efficient methods for chalcogen‐containing compound synthesis . Ynediones were considered an appropriate synthetic precursor of heterocyclic hemiketal‐containing α,β‐unsaturated ketones, which could be obtained easily from α‐hydroxyketones based on previous report (Scheme ) . Combined with different heteroatom reagents, the reactions of ynediones could probably produce different heterocyclic compounds.…”