A Cascade C-H-Functionalization/Cyclization Reaction of Indoles with α-Halo or α-Sulfonyloxy Ketones for the Synthesis of Dihydropyrimidoindolone Derivatives
作者:Zi-Jun Wu、Ya-Qiong Li、Zhi-Zhen Huang
DOI:10.1002/ejoc.201600885
日期:2016.11
A new cascade C–H-functionalization/cyclization reaction of N-carbamoylindoles 1 with α-halo, α-mesyloxy, or α-tosyloxy ketones 2 has been developed under rhodium(III) catalysis, leading to dihydropyrimido[1,6-a]indolone derivatives 3 in moderate to excellent yields.
α-MsO/TsO/Cl Ketones as Oxidized Alkyne Equivalents: Redox-Neutral Rhodium(III)-Catalyzed CH Activation for the Synthesis of N-Heterocycles
作者:Da-Gang Yu、Francisco de Azambuja、Frank Glorius
DOI:10.1002/anie.201310272
日期:2014.3.3
α‐Halo and pseudohalo ketones are used for the first time as C(sp3)‐based electrophiles in transition‐metal‐catalyzed CHactivation and as oxidizedalkyneequivalents in RhIII‐catalyzed redox‐neutral annulations to generate diverse N‐heterocycles. This transformation is efficient and scalable. Due to the mild reaction conditions, a variety of functional groups could be tolerated.
A New Application of Hypervalent Iodine (λ<sup>5</sup>) Reagents with Organosulfonic Acids for Direct α-Organosulfonyloxylation Carbonyl Compounds
作者:Krishnacharya Akamanchi、Ulhas Mahajan
DOI:10.1055/s-2008-1072508
日期:——
Hypervalent iodine (λ 5 ) reagents in combination with P-toluenesulfonic acid when reacted with ketones under reflux temperature in acetonitrile gave α-tosyloxy ketones in moderate to excellent yields. The reaction was developed further for both ketones and dicarbonyl compounds using Dess-Martin periodinane reagent in combination with P-toluenesulfonic acid and methanesulfonic acid, to give mono-α-tosyloxy
Construction of Pyridazine Analogues <i>via</i>
Rhodium-mediated C-H Activation
作者:Chao Yang、Feifei Song、Jiean Chen、Yong Huang
DOI:10.1002/adsc.201700905
日期:2017.10.25
Herein a rhodium (III)‐mediated catalysis was demonstrated for approaching the structurally divergent N,N‐bicyclic pyridazine analogues. The pyrazolidinone moiety was used to direct the ortho C−H activation and this led to a general synthesis of benzopyridazine analogues with satisfactory yields. The crucial effect of the base was illustrated in the sequential dehydration process. For mechanistic insight
One-Pot Protocol for Synthesis of<font>α</font>-Organosulfonyloxy Ketones from Secondary Alcohols Using Hypervalent Iodine(V)–Mediated Oxidations
作者:Swapnil S. Deshmukh、Sameerana N. Huddar、Krishnacharya G. Akamanchi
DOI:10.1080/00397910902730952
日期:2009.7.29
Abstract α-Tosyloxy ketones and α-mesyloxy ketones were directly prepared from alcohols in one pot by treatment with hypervalentiodine(V) reagents in combination with p-toluenesulfonic acid and methanesulfonic acid, respectively, in moderate to good yields. Reactions were also feasible under solvent-free conditions.