A cascade alkylarylation reaction of 2-isocyanobiphenyls with simple alkanes for 6-alkyl phenanthridines via dual C(sp<sup>3</sup>)–H/C(sp<sup>2</sup>)–H functionalizations
A cascade alkylarylation reaction of 2-isocyanobiphenyls with simple alkanes for 6-alkyl phenanthridines has been developed through dual C(sp3)âH/C(sp2)âH functionalizations. The synthetic method has the advantages of high yields, good compatibility of functional groups and mild reaction conditions, although very unreactive alkanes were involved in the reaction. A plausible mechanism through both copper-catalyzed and DTBP mediated pathways has also been proposed.
Fe-catalyzed cascade addition/cyclization of 2-biphenyl isocyanides with toluenes for the synthesis of 6-benzylated phenanthridines has been reported. Di-tert-butyl peroxide (DTBP) was employed as both a radical initiator and an oxidant. The procedure tolerates various functional groups, providing the corresponding products in moderate to good yields. The proposed mechanism involves the cascade addition
Visible-light-promoted synthesis of phenanthridines via an intermolecular isocyanide insertion reaction
作者:Hui Zhou、Xin Zhao Deng、Ai Hua Zhang、Ren Xiang Tan
DOI:10.1039/c6ob02113a
日期:——
conditions. The reaction was shown to proceed through an electron transfer sequence by mechanistic experiments, and thus enabled the efficient production of 24 compounds, each with one new intramolecular aromatic ring obtained. The synthesized compounds were tested to embody good antitumor, antimicrobial and neuraminidase inhibitory activities.
the generation of phosphinoyl radicals from the combination of diphenyliodonium salt (Ph2I+,–OTf) with triethylamine (Et3N) in the presence of secondary phosphine oxides is reported. By employing this practical and simple approach, a large variety of 6-phosphorylated phenanthridines have been synthesized through the addition of phosphinoyl radicals to isonitriles as radical acceptors. The reaction works
报道了在仲氧化膦的存在下,由二苯基碘鎓盐(Ph 2 I +,– OTf)与三乙胺(Et 3 N)结合生成膦酰基的新颖有效方法。通过采用这种实用且简单的方法,已经通过向膦腈中添加膦酰基作为自由基受体而合成了多种6-磷酸化的菲啶。在没有任何过渡金属或光催化剂的情况下,该反应可顺利进行。在电子顺磁共振(EPR)和密度泛函理论(DFT)计算的基础上,讨论了该反应的机理。
Transformations of Isonitriles with Bromoalkanes Using Photoredox Gold Catalysis
作者:Samantha Rohe、Terry McCallum、Avery O. Morris、Louis Barriault
DOI:10.1021/acs.joc.8b01380
日期:2018.9.7
Recently, photoredox catalysis has emerged as a powerful tool for the construction of C–C bonds with few protocols for alkylative heterocycle synthesis through isonitrile addition. Herein, we describe the photocatalytic generation of alkyl radicals from unactivated bromoalkanes as part of an efficient cross-coupling strategy for the diversification of isonitriles using a dimericgold(I) photoredox catalyst