Deacetylative Aryl Migration of Diaryliodonium Salts with C(sp<sup>2</sup>)–N Bond Formation toward <i>ortho</i>-Iodo <i>N</i>-Aryl Sulfonamides
作者:Huangguan Chen、Limin Wang、Jianwei Han
DOI:10.1021/acs.orglett.0c01024
日期:2020.5.1
An unprecedented approach of metal-free C(sp2)-N bond formation via deacetylation/intramolecular aryl migration is demonstrated with novel N-sulfonamide substituted diaryliodonium salts. The reaction provides a variety of ortho-iodo N-aryl sulfonamides. The products were employed in several coupling reactions to afford useful diarylamine scaffolds. Furthermore, the key intermediates of zwitterionic
A palladium-catalyzed intermolecular dearomative formal [4+2] annulation of phenols with propargyl electrophiles is reported, enabling substituent-controlled regiodivergent synthesis of a wide range of skeletally diverse spirocyclohexadienones with good yields. The regiodivergence could be precisely controlled by adjusting the steric hindrance of O- and N-substituents from binucleophilic substrates
A palladium-catalyzed asymmetric annulative dearomatization of phenols with butene dicarbonate is reported, enabling twofold decarboxylativeallylation to regioselectively produce a range of spirocyclohexadienones with 29–95% yields and 74–99% ee. A catalytic dearomative formal [4 + 2] cyclization of 1,1′-biphenyl-2,4′-diols delivered spiro[chromane-4,1′-cyclohexane]-2′,5′-dien-4′-ones with high enantioselectivity
This study presents a convenient approach to the synthesis of indole- and benzofuran-based benzylic sulfones using unactivated alkynes containing aryl iodides and sodium sulfinates under visible light irradiation. The procedure involves a sequential series of dehalogenation, carbo-cyclization, and radical sulfonylation. Plausible insights into the reaction mechanism are derived from control experiments