control experiments. The reaction of cinnamic acids with (diacetoxyiodo)benzene in 1,2-dichloroethane in the presence of sulfuricacid provides an easy and direct access to the α-keto diacetate framework. This hypervalent iodine mediated oxidative reaction involves a tandem sequence of aryl migration, insertion of an oxygen atom, decarboxylation and diacetoxylation. A reaction mechanism is proposed and
Metal-Free Reductive Cleavage of C−O σ-bonds in Acyloin Derivatives by an Organic Neutral Super-Electron-Donor
作者:Sylvain P. Y. Cutulic、Neil J. Findlay、Sheng-Ze Zhou、Ewan J. T. Chrystal、John A. Murphy
DOI:10.1021/jo901815t
日期:2009.11.20
Neutral organic electron-donor 7, formally a pyridinylidene carbene dimer, effects reductivecleavage of C−O σ-bonds in acyloin derivatives Ar(CO)CRR′OX (X = OAc, OPiv, OBz, OMs) and this represents the first cleavage of C−O σ-bonds by a neutral organic electron-donor. The methodology is applicable to a large array of substrates and the reduced counterparts were isolated in good to excellent yields
Selective Synthesis of Acylated Cross-Benzoins from Acylals and Aldehydes via <i>N</i>-Heterocyclic Carbene Catalysis
作者:Kou Onodera、Ryo Takashima、Yumiko Suzuki
DOI:10.1021/acs.orglett.1c01134
日期:2021.6.4
cross-benzoins) was achieved via selective N-heterocyclic carbene-catalyzed cross-benzoin reactions using acylals as aldehyde equivalents. Thus, the combination of ortho-substituted phenyl acylals and aromatic/aliphatic aldehydes as coupling substrates using bicyclic triazolium salts as precatalysts and potassium carbonate as a base in THF at reflux temperature selectively yielded O-acyl cross-benzoins.