Search

An efficient one-pot procedure for the synthesis of propargyl alcohol derivatives from allyl alcohol derivatives has been developed. The key to this transformation from a C-C double bond to a C-C triple bond is that hydrogen bromide elimination from 1,2-dibromoalkanes that contain a neighboring oxygen functional group is promoted by the inductive electron-withdrawing effect of the oxygen functional group. In the one-pot reaction, tetrabutylammonium hydroxide was the best base, and the addition of molecular sieves 13X also promoted the reaction. [ABSTRACT FROM AUTHOR]

1,1-Dihydroperoxides were converted into 1,2,4,5-tetraoxanes through condensation with the corresponding ketones in 36-91% yields using phosphomolybdic acid as the catalyst and anhydrous MgSO4 as the water scavenger. [ABSTRACT FROM AUTHOR]

An efficient catalytic system for oxybromination of phenols under mild conditions has been developed, which utilizes sodium nitrite as the catalyst, dioxygen or air as the terminal oxidant, aqueous hydrobromic acid or molecular bromine as the bromine resource. From both the atom-economic and environmental points of view, the developed protocol is expected to provide a valuable synthetic method for practical applications in laboratory or industry. [ABSTRACT FROM AUTHOR]

We report that ethylbenzenes can be directly oxidized to the corresponding α-keto esters with molecular oxygen in the presence of 48% aqueous HBr under visible light irradiation. This synthetic procedure is the first example for direct preparation of the corresponding a-keto esters from ethylbenzenes. [ABSTRACT FROM AUTHOR]

A triphasic phase-vanishing (PV) system comprised of an alkane, perfluorohexanes, and bromine was successfully combined by photoirradiation to efficiently generate hydrogen bromide, which underwent radical addition with 1-alkenes in the hydrocarbon layer to afford terminal bromides in high yields. [ABSTRACT FROM AUTHOR]

A triphasic phase-vanishing (PV) system comprised of an alkane, perfluorohexanes, and bromine was successfully combined by photoirradiation to efficiently generate hydrogen bromide, which underwent radical addition with 1-alkenes in the hydrocarbon layer to afford terminal bromides in high yields. [ABSTRACT FROM AUTHOR]