Sunlight-Driven Decarboxylative Alkynylation of α-Keto Acids with Bromoacetylenes by Hypervalent Iodine Reagent Catalysis: A Facile Approach to Ynones
作者:Hui Tan、Hongji Li、Wangqin Ji、Lei Wang
DOI:10.1002/anie.201503479
日期:2015.7.13
A novel and practical decarboxylativealkynylation of α‐keto acids with bromoacetylenes is catalyzed by hypervalent iodine(III) reagents when irradiation by sunlight at room temperature. The product ynones are generated in good yields. Experiments show that results obtained with blue light (λ=450–455 nm) are comparable to those obtained when using sunlight. Mechanistic studies demonstrate that the
A palladium-catalyzed procedure for the decarboxylative-carbonylation of phenylpropiolic acid with iodobenzenes to the corresponding alkynones with formic acid as carbon monoxide source has been developed. Various alkynones were produced in moderate to good yields.
A novel and efficient approach for the synthesis of functionalized isoxazoles viapalladium-catalyzed cascade annulation/allylation of alkynyl oxime ethers with allyl halides has been established. The present protocol exhibits mild reaction conditions, good functional group compatibility, and convenient operation. Moreover, scalability was performed and further decoration of the isoxazole product was
A magnetically separable palladiumcatalyst was simply synthesized through a wet impregnation incorporating palladiumnanoparticles and superparamagnetic Fe3O4 nanoparticles in KBH4 solution, which is a highly efficient catalyst for the carbonylative Sonogashira coupling reaction of aryl iodides with terminal alkynes under phosphine-free conditions. This catalyst is completely magnetically recoverable