Tandem dual C(sp3)-H/C(sp2)-H functionalization: a radical cyclization of 2-isocyanobiphenyl with ether to 6-alkylated phenanthridine
作者:ChangDuo Pan、Jie Han、Zhu ChengJian
DOI:10.1007/s11426-014-5118-7
日期:2014.8
A simple and efficient radical coupling of 2-isocyanobiphenyl with ethers was developed, providing a variety of 6-alkylated phenanthridines. Both cyclic and acyclic ethers are suitable substrates for this transformation, which comprised the functionalization of two C-H bonds: the sp3 C-H of ether and sp2 C-H of phenyl group. The kinetic isotope effect (KIE) revealed that the cleavage of sp3 C-H bond would be involved in the rate-determining step.
proceeding through dual C–H bond cleavage and dual C–C bond formation. The procedure tolerates a series of functional groups, such as methyl, fluoro, chloro, acetyl, methoxy carbonyl, cyano, and trifluoromethyl. Thus, it represents a facile pathway leading to 6-substitutedphenanthridine derivatives. The addition of radical to the isonitrile followed by a radical aromatic cyclization is involved in this