The Iridium-catalyzed enantioselective couplingreaction of vinyl azides and allylic electrophiles is presented and provides access to β-chiral carbonyl derivatives. Vinyl azide are used as acetamide enolate or acetonitrile carbanion surrogates, leading to γ,δ-unsaturated β-substituted amides as well as nitriles with excellent enantiomeric excess. The products are readily transformed into chiral N-containing
Photoswitchable Regiodivergent Azidation of Olefins with Sulfonium Iodate(I) Reagent
作者:Dodla S. Rao、Thurpu R. Reddy、Aakanksha Gurawa、Manoj Kumar、Sudhir Kashyap
DOI:10.1021/acs.orglett.9b03910
日期:2019.12.20
Photoswitchable strategy for selective azidation of structurally diverse olefins under transition-metal-free conditions is reported. The unprecedented reactivity of trimethylsulfonium [bis(azido)iodate(I)] species under visible light allows radical azidooxygenation of the C═C π bond with distinctive selectivity. In the absence of visible light, the reaction proceeds through an ionic intermediate which
Iodoazidation of Alkenes by Using Iodine Pentafluoride–Pyridine–Hydrogen Fluoride and Trimethylsilyl Azide
作者:Shoji Hara、Tatsuki Hiraoka、Shohei Yano
DOI:10.1055/s-0035-1561374
日期:——
Iodoazidation of alkenes was carried out by using iodine pentafluoride–pyridine–hydrogen fluoride and trimethylsilyl azide. In the reactions of terminal alkenes, anti-Markovnikov products were formed selectively. Cyclohexene gave a mixture of cis- and trans-adducts. These results suggest the involvement of radical species in the reaction. Iodoazidation of alkenes was carried out by using iodine pentaf
A method for the synthesis of amide‐containing molecules was developed using vinylazides as an enamine‐type nucleophile towards carbon electrophiles, such as imines, aldehydes, and carbocations that were generated from alcohols in the presence of BF3⋅OEt2. After nucleophilic attack of the vinylazide, a substituent of the resulting iminodiazonium ion intermediate migrates to form a nitrilium ion,
A protocol to link alcohols with vinyl azides has been established through fluoro- or bromo-alkoxylation of vinyl azides to provide α-alkoxy-β-haloalkyl azides. A series of primary and secondary alcohols including natural products and their derivatives such as sugars and steroids were successfully anchored with vinyl azides. The as-prepared cyanine dye linked testosterones were capable of rapid cell