Bis(pyridine)iodonium Tetrafluoroborate (IPy2BF4): A Versatile Oxidizing Reagent
作者:José Barluenga、Francisco González-Bobes、Marcelo C. Murguía、Sreenivasa R. Ananthoju、José M. González
DOI:10.1002/chem.200400136
日期:2004.9.6
The use of bis(pyridine)iodoniumtetrafluoroborate (IPy(2)BF(4)) as an oxidizing agent towards different types of alcohols is reported. The observed reactivity involves different reaction pathways, as a function both of the structures of the starting materials and of the experimental conditions. Interestingly, the title iodine-containing compound is capable of a tuneable reaction with simple cycloalkanols
Site-selective and product chemoselective aliphatic C–H bond oxidation of 1,2-diols and of polyhydroxylated substrates using iron and manganese catalysts and hydrogen peroxide as terminal oxidant is described. The reaction capitalizes on the use of fluorinated alcohol solvents such as 2,2,2-trifluoroethanol (TFE) and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), which exert a strong polarity reversal in
Efficient and mild: The selective monoallylation of 1,2‐diols was successfully developed with Pd/Snbimetalliccatalysis in good to excellent yields. This process was carried out with high substrate tolerance under mild conditions (see scheme). The catalyst system achieved the quite high chemoselectivity even in the presence of a 1:1 mixture of the 1,2‐diol and mono‐ol.
The reaction of 1,2-diols with dimethyl sulfoxide-catalytic molybdenum peroxide in refluxing toluene generally resulted in monoprotection of diols to give 2-methylthiomethoxy-l-ols (Course A) Exceptionally, a) cis-1,2-cyclooctanediol and benzopinacol, and b) 1,2-cyclododecanediol caused C–C bond cleavage (Course B) and monooxidation (Course C), respectively as Scheme 1.
Enantioselective Propargylation of Polyols and Desymmetrization of <i>meso</i>
1,2-Diols by Copper/Borinic Acid Dual Catalysis
作者:Ren-Zhe Li、Hua Tang、Ke R. Yang、Li-Qiang Wan、Xia Zhang、Jie Liu、Zhengyan Fu、Dawen Niu
DOI:10.1002/anie.201703029
日期:2017.6.12
A copper/borinic acid dual catalytic reaction enabled the enantioselective propargylation of aliphatic polyols. Readily available reagents and catalysts were used in this transformation, which displayed good to excellent chemo‐ and stereoselectivity for a broad array of substrates. The method was also applicable to the desymmetrization of meso 1,2‐diols to furnish products with three stereogenic centers