Catalytic Oxidation of Alkynes into 1, 2‐Diketone Derivatives by Using a PdII/Lewis‐Acid Catalyst. Issue 1 (29th November 2017)

• Record Type: Journal Article
• Authors: Xue, Jing‐Wen; Zeng, Miao; Hou, Xianfei; Chen, Zhuqi; Yin, Guochuan
• Is Part Of: Asian journal of organic chemistry. Volume 7:Issue 1(2018)
• Page Start: 212
• Page End: 219
• Publication Date: 2017-11-29
• Subjects: alkynes -- Lewis acids -- oxidation -- palladium -- synthetic methods; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; 547.005
• DOI: 10.1002/ajoc.201700556
• Languages: English
• ISSNs: 2193-5807

Abstract

Abstract: A new synthetic method has been developed for the efficient oxidation of alkynes into 1, 2‐diketones by using a Pd II /Lewis acid catalytic system using DMSO as the oxidant and solvent. Under our optimized reaction conditions, this approach tolerated a variety of functional groups and afforded 1, 2‐diketone derivatives in 62–99 % yields. This work demonstrated that the addition of non‐redox‐active metal ions, such as Al III, to Pd(OAc)2 could dramatically improve its catalytic efficiency for alkyne oxidation, whilst reactions with Pd(OAc)2 alone were sluggish and afforded a low yield of the corresponding diketone. Based on NMR and UV/Vis analysis, a heterobimetallic Pd II /Al III species was proposed for alkyne oxidation by adding AlCl3 to Pd(OAc)2 in DMSO. The catalytic efficiency of the Pd II species was improved by the linkage of Al III to the Pd II species, which made the Pd II species more electron deficient. This method may have the potential to become a simple, efficient procedure for the synthesis of 1, 2‐diketone derivatives. Abstract : LA Confidential : A new synthetic method is reported for the oxidation of alkynes catalyzed by a Pd II /Lewis Acid system in DMSO as the oxidant. This method provides efficient access to 1, 2‐diketones in good‐to‐excellent yields.