Electrosynthesis of Dihydropyrano[4,3‐
<i>b</i>
]indoles Based on a Double Oxidative [3+3] Cycloaddition
作者:Subin Choi、Jinhwi Park、Eunsoo Yu、Jeongwoo Sim、Cheol‐Min Park
DOI:10.1002/anie.202003364
日期:2020.7.13
methylene compounds followed by tandem 6π‐electrocyclization leading to the synthesis of dihydropyrano[4,3‐b ]indoles and 2,3‐dihydrofurans. The radical–radical cross‐coupling of the radical species generated by anodic oxidation combined with the cathodic generation of the base from O2 allows for mild reaction conditions for the synthesis of structurally complex heterocycles.
氧化性[3 + 3]环加成反应为六元环形成提供了一条有效途径。该方法是基于吲哚/烯胺与活性亚甲基化合物的电化学氧化偶联,然后串联6π-电环化反应生成二氢吡喃并[4,3- b ]吲哚和2,3-二氢呋喃而实现的。阳极氧化产生的自由基与自由基从O 2产生的自由基之间的自由基交叉偶联为合成结构复杂的杂环提供了温和的反应条件。
Gold(I)‐Catalyzed Enantioselective Desymmetrization of 1,3‐Diols through Intramolecular Hydroalkoxylation of Allenes
作者:Weiwei Zi、F. Dean Toste
DOI:10.1002/anie.201508331
日期:2015.11.23
A gold(I)‐catalyzedenantioselectivedesymmetrization of 1,3‐diols was achieved by intramolecularhydroalkoxylation of allenes. The catalyst system 3‐F‐dppe(AuCl)2 /(R)‐C8‐TRIPAg proved to be specifically efficient to promote the desymmetrizing cyclization of 2‐aryl‐1,3‐diols, which have proven challenging substrates in previous reports. Multisubstituted tetrahydrofurans were prepared in good yield
Metal-Free Synthesis of Indolopyrans and 2,3-Dihydrofurans Based on Tandem Oxidative Cycloaddition
作者:Subin Choi、Hyeonji Oh、Jeongwoo Sim、Eunsoo Yu、Seunghoon Shin、Cheol-Min Park
DOI:10.1021/acs.orglett.0c01896
日期:2020.7.17
transfer between coupling partners followed by cage collapse allows highly selective cross-coupling while employing only equimolar amounts of coupling partners. Moreover, the mechanistic manifold was expanded for the functionalization of enamines to give the stereoselective synthesis of 2,3-dihydrofurans. This iodine-mediatedoxidative coupling features mild conditions and fast reaction kinetics.