1234673-90-5Relevant articles and documents
Cu-Photoredox-catalyzed C(sp)-C(sp3) coupling of redox-active esters with terminal alkynes
Zhang, Dayong,Zhang, Yajing
supporting information, p. 4479 - 4483 (2020/10/20)
Visible-light-induced C(sp)-C(sp3) coupling of redox-active esters with terminal alkynes has been developed. The activation of carboxylic acids as their redox-active ester derivatives was important for this decarboxylative alkynylation. The strategy established here facilitates the straightforward introduction of triple-bonded functional groups and avoids additional photocatalysts. A wide range of primary, secondary and tertiary acids can be converted into the target products; so this reaction exhibits a broad substrate scope and tolerance of functional groups. Mechanistic experiments suggested that this reaction may undergo a radical process. Under mild reaction conditions, a copper acetylide ligand as a photocatalyst delivered an electron to redox-active ester derivatives, and generated alkyl radicals. The radicals reacted with Cu(ii) to deliver a Cu(iii) complex, and then reductive elimination gave the products.
Palladium-catalyzed decarboxylative coupling of alkynyl carboxylic acids with benzyl halides or aryl halides
Zhang, Wen-Wu,Zhang, Xing-Guo,Li, Jin-Heng
experimental part, p. 5259 - 5264 (2010/10/04)
(Figure presented) The synthesis of internal benzyl alkynes and 1,2-diarylalkynes has been developed via palladium-catalyzed decarboxylative coupling reactions of alkynyl carboxylic acids with benzyl chlorides or aryl halides. In the presence of Pd(OAc)2 and Xphos (L3), alkynyl carboxylic acids smoothly underwent the reaction with various benzyl halides, providing the corresponding benzyl alkynes in moderate to good yields. It is noteworthy that the optimal conditions are compatible with a wide range of aryl halides including less active aryl chlorides.
