Rhodium(III)-Catalyzed<i>ortho</i>Alkenylation of<i>N</i>-Phenoxyacetamides with<i>N</i>-Tosylhydrazones or Diazoesters through CH Activation
作者:Fangdong Hu、Ying Xia、Fei Ye、Zhenxing Liu、Chen Ma、Yan Zhang、Jianbo Wang
DOI:10.1002/anie.201309650
日期:2014.1.27
A coupling reaction of N‐phenoxyacetamides with N‐tosylhydrazones or diazoestersthrough RhIII‐catalyzed CHactivation is reported. In this reaction, ortho‐alkenyl phenols were obtained in good yields and with excellent regio‐ and stereoselectivity. Rh–carbene migratory insertion is proposed as the key step in the reaction mechanism.
Palladium-catalyzed synthesis of benzofurans via C–H activation/oxidation tandem reaction and its application to the synthesis of decursivine and serotobenine
A new palladium-catalyzed method for the synthesis of benzofurans by reaction of 2-hydroxystyrenes and iodobenzenes via a CâH activation/oxidation tandem reaction has been unprecedentedly discovered. By using this strategy, the overall synthetic efficiency of the synthesis of decursivine and its analogues was indeed improved. Preliminary mechanistic studies shed light into the possible mechanisms.
The transition-metal-free lactonization of heteroaryl and alkenyl C–H bonds with carbon dioxide is reported to synthesize important coumarin derivatives in moderate to excellent yields. These redox-neutral reactions feature a broad substrate scope, good functional group tolerance, facile scalability, and easy product derivatization.
Chiral Brønsted acid catalyzed intermolecular Friedel–Crafts alkylation of styrenes with indoles: construction of all-carbon quaternary stereocenters
作者:Ming-Li Li、Dian-Feng Chen、Shi-Wei Luo、Xiang Wu
DOI:10.1016/j.tetasy.2015.01.005
日期:2015.2
A chiralBrønstedacidcatalyzedFriedel–Craftsreaction of terminal 1,1-diaryalkenes with indoles is described. This reaction provides indole derivatives with acyclic all-carbon quaternary stereocenters in excellent yields and with excellent enantioselectivities, and features high atom efficiency without the generation of side products.
An efficient asymmetric hydroesterfication of diarylmethyl carbinols is developed for the first time with a Pd‐WingPhos catalyst, resulting in a series of chiral 4‐aryl‐3,4‐dihydrocoumarins in excellent enantioselectivities and good yields. The method features mild reaction conditions, a broad substrate scope, use of easily accessible starting materials, and low palladium loadings. A plausible stereochemical