New method for C–H arylation/alkylation at α-position of cyclic aliphatic ethers by iron-oxide mediated reaction
作者:Parvinder Pal Singh、Satish Gudup、Hariprasad Aruri、Umed Singh、Srinivas Ambala、Mahipal Yadav、Sanghapal D. Sawant、Ram A. Vishwakarma
DOI:10.1039/c1ob06660a
日期:——
We report a new and efficient iron oxide catalyzed cross-coupling reaction between organometallic species such as alkyl/arylmagnesium halides or organolithium species and α-hydrogen bearing cyclic unbranched and branched aliphatic ethers via activation of C(sp3)–H. In the presence of 1 mol% of iron oxide, five and six membered unbranched cyclic ethers such as tetrahydrofuran and tetrahydropyran gave
The regioselective Heck arylation of unsaturated alcohols is utilized as the key step in a convenient one-pot procedure for the production of 2,2-disubstituted tetrahydrofurans and tetrahydropyrans. The arylation reaction is effected with a palladium-diphosphine catalyst alongside a hydrogen bond donor; this is followed by the introduction of a Brønsted acid to the reaction mixture, affording the oxygen heterocycles in moderate yields.