Herein, we report a rhodium catalyzed directing‐group free regioselective C−H allylation of simple arenes. Readily available gem‐difluorinated cyclopropanes can be employed as highly reactive allyl surrogates via a sequence of C−C and C−F bondactivation, providing allyl arene derivatives in good yields with high regioselectivity under mild conditions. The robust methodology enables facile late‐stage
A Pd-catalyzed ring-opening sulfonylation of gem-difluorocyclopropanes is reported. This protocol involves C-C bond cleavage, β-F elimination, and allylic coupling to form corresponding 2-fluoroallylic sulfones efficiently with Z-selectivity. Different substrates bearing diverse functional groups are tolerated. Moreover, this method is successfully used for the late-stage derivation of several bioactive
Palladium-Catalyzed Synthesis of Functionalized Indoles by Acylation/Allylation of 2-Alkynylanilines with Three-Membered Rings
作者:Weiliang Yuan、Xiaojiao Li、Zisong Qi、Xingwei Li
DOI:10.1021/acs.orglett.2c00246
日期:2022.3.25
Palladium-catalyzed synthesis of 3-acyl and -allyl indoles has been realized by merging nucleophilic cyclization of ortho-alkynylanilines with ring opening of three-memberedrings such as cyclopropenones and gem-difluorinated cyclopropanes. These functionalized indoles were obtained in moderate to high yields with high stereoselectivity in both cases. This protocol provides an alternative method toward
switchable in allyl–allyl cross-coupling reactions between gem-difluorinated cyclopropanes and allylboronates. The controlled terminal/internal regioselectivity arises from the fine-tuning of the rhodium catalytic system. Fluorinated 1,3-dienes, 1,4-dienes and 1,5-dienes are therefore produced in good yields with respectively isomerized terminal, internal, and terminal regioselectivity.
incorporate the fluoroallyl motif into different alkenyl C–H sites is disclosed. gem-Difluorinated cyclopropanes are employed as fluoroallyl sources via rhodium-catalyzed C–C bond activation. This strategy can provide two regioisomeric fluorinated skipped dienes in good yields with excellent site-selectivity. The resulting products can serve as useful building blocks to access various fluorine-containing molecules