of copper, rhodium, and gold formulate a one‐pot multistep pathway, which directly gives 2,5‐dihydropyrroles starting from terminal alkynes, sulfonyl azides, and propargylic alcohols. Initially, copper‐catalyzed 1,3‐dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1‐sulfonyl‐1,2,3‐triazoles, which then react with propargylic alcohols under the catalysis of rhodium. The resulting
Diethylzinc-Mediated Radical 1,2-Addition of Alkenes and Alkynes
作者:Xin Li、Songtao He、Qiuling Song
DOI:10.1021/acs.orglett.1c00669
日期:2021.4.16
A novel diethylzinc-mediated radical 1,2-addition of perfluoroalkyl iodides to unactivatedalkenes and alkynes is presented, which demonstrates a novel way to generate an ethyl difluoroacetate radical. This method is highly efficient and gives full conversions of the substrates, high yields of the products, and negligible byproducts and requires no column chromatography purifications. The mild conditions
1-Sulfonyl-1,2,3-triazoles, readily prepared from terminal alkynes and sulfonylazides, react with allenes in the presence of a nickel(0) catalyst to produce the corresponding isopyrroles. The initially produced isopyrroles are further converted to a wide range of polysubstituted pyrroles through double bond transposition and Alder-ene reactions.
Water-soluble cobalt(III) porphyrin complexes were found to promote the hydration of terminal alkynes to give methyl ketones. The alkynehydration proceeded in good to excellent yield with 0.1 to 2 mol % cobaltcatalyst 1 and was compatible with the presence of acid/base- or redox-sensitive functional groups such as alkyl silyl ethers; allyl ethers; trityl ethers; benzyl ethers; carboxylic esters;
A novel Ag(I)-catalyzed benzylic amination reaction with in situ generation of NH-1,2,3-triazoles for N2-substituted 1,2,3-triazole scaffolds is described. This protocol is achieved with easily accessible substrate, broad functional group, good regioselectivity, thus providing the efficient and practical method to diverse N2-substituted 1,2,3-triazole rings with moderate to good yields.