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.
rapid microwave-assisted approach for the synthesis of phenanthridine derivatives from the radical insertion/cyclization reaction of biphenyl isocyanides with a C(sp3)–H bond adjacent to a heteroatom has been developed. The protocol achieves wide substrate scope and good to excellent yields. The kinetic isotope effect (KIE) studies, radical inhibition studies, and Hammett plot analysis clearly disclose
Boryl Radicals-Triggered Selective C–H Functionalization for the Synthesis of Diverse Phenanthridine Derivatives
作者:Ao Guo、Jia-Bin Han、Xiang-Ying Tang
DOI:10.1021/acs.orglett.8b00642
日期:2018.4.20
DMF with isocyanides is developed to deliver diverse phenanthridine derivatives in good to excellent yields. The substrate scope is broad, and a wide range of functional groups are tolerated under the standard conditions. The rapid removal of HBPin species by 4-cyanopyridine 1-oxide provides the driving force for this reaction. This new method should make boryl radicals widely applicable in organic synthesis