oxidant-free direct cyanoalkylarylation of isocyanides with AIBN has been developed under mild conditions. This strategy provides an elusive and rapid access to a wide range of cyano-containing phenanthridinederivatives in good yields via a one-pot alkylation/cyclization radical-cascade process. The mild reaction conditions together with no need of any catalyst, base, or oxidant make this protocol environmentally
Direct synthesis of 6-sulfonylated phenanthridines via silver-catalyzed radical sulfonylation-cyclization of 2-isocyanobiphenyls
作者:Manjula Singh、Arvind K. Yadav、Lal Dhar S. Yadav、Rana Krishna Pal Singh
DOI:10.1016/j.tetlet.2018.07.024
日期:2018.8
straightforward synthesis of 6-sulfonylated phenanthridines via silver-catalyzed sequential radical insertion, cyclization and aromatization of 2-isocyanobiphenyls is reported. The protocol does not require a phenanthridine scaffold as a substrate and presents a highly regioselectivesynthesis of 6-alkyl/arylsulfonyl phenanthridines. The protocol utilizes readily available and easy to handle sodium sulfinates
A metal-free radical oxidative decarboxylation/cyclization of acyl peroxides and 2-isocyanobiphenyls was achieved, leading to 6-aryl phenanthridines as well as 6-alkyl phenanthridines in moderate to good yields. The procedure featured simple conditions and was metal-free and base free. It represents a practical approach to access 6-aryl/alkyl phenanthridines.
A practical and environmentally friendly strategy for generatingalkoxycarbonylradicalsfrom readily available carbazates under metal‐free conditions has been developed. In the presence of tetrabutylammonium iodide and tert‐butyl hydroperoxide, 2‐isocyanobiphenyls smoothly underwent radical alkoxycarbonylation with carbazates to afford phenanthridine‐6‐carboxylates.
A photocatalyst-free, light promoted sequential radical addition/annulation of 2-isocyanobiphenyls to 6-trifluoromethyl phenanthridines with high efficiency is presented.