Substitution reactions of alkanesulfonyl derivatives: direct substitution vs. elimination-addition mechanisms in substitution reactions of alkyl .alpha.-disulfones
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
with exclusive regioselectivity and stereoselectivity. Functional application of such a resultant product by oxidative addition and epoxidation is also explored. Notably, the treatment of a pyrroline-fused N-glycoside (3a) with TMSOTf efficiently leads to an interesting unexpected C-nucleoside (9) via a TMSOTf-inducing ring opening/acetyl migration/ringclosingreaction sequence.
Ru(ii)-catalyzed intermolecular ortho-C–H amidation of aromatic ketones with sulfonyl azides
作者:M. Bhanuchandra、M. Ramu Yadav、Raja K. Rit、Malleswara Rao Kuram、Akhila K. Sahoo
DOI:10.1039/c3cc41915k
日期:——
Ru(II)-catalyzed intermolecular ortho-CâH amidation of weakly coordinating aromatic ketones with sulfonyl azides is reported. The developed reaction protocol can be extended to various substituted aromatic ketones to afford a wide range of desired CâN bond formation products in good yields.
Iridium-Catalyzed <i>ortho</i>-C(sp<sup>2</sup>)–H Amidation of Benzaldehydes with Organic Azides
作者:Delong Mu、Xinmou Wang、Gong Chen、Gang He
DOI:10.1021/acs.joc.7b00531
日期:2017.4.21
ortho-C(sp2)–H amidation reaction of benzaldehydes with organic azides has been developed. A catalytic amount of 3,5-di(trifluoromethyl)aniline was used to promote the Ir-catalyzed directed C–H amination reaction through a transient aldimine intermediate. This reaction tolerates a broad scope of benzaldehyde substrates and works well with a range of aryl- and alkylsulfonyl azides.
Intermolecular C–H Amidation of Alkenes with Carbon Monoxide and Azides via Tandem Palladium Catalysis
作者:Zheng-Yang Gu、Yang Wu、Xiaoguang Bao、Ji-Bao Xia、Feng Jin
DOI:10.1055/a-1401-4486
日期:2021.9
alkenes with carbonmonoxide and organic azides has been developed for the synthesis of alkenyl amides. The reaction proceeds efficiently without an ortho-directing group on the alkene substrates. Nontoxic dinitrogen is generated as the sole by-product. Computational studies and control experiments have revealed that the reaction takes place via an unexpected mechanism by tandem palladium catalysis.