以前未开发的将格利雅(Grignard)添加到羟吲哚中的方法通过一锅芳构化驱动的脱水途径,以高收率提供了一种区域特异性的方法,用于2-和2,3-二取代的吲哚衍生物。这种方法可以方便地制备用作烯丙基[1,2- a ]吲哚和咔唑的正交合成的闭环复分解(RCM)前体的二烯丙基吲哚。该方法的合成效用通过微管蛋白抑制剂和天然存在的咔唑生物碱的合成来说明。
以前未开发的将格利雅(Grignard)添加到羟吲哚中的方法通过一锅芳构化驱动的脱水途径,以高收率提供了一种区域特异性的方法,用于2-和2,3-二取代的吲哚衍生物。这种方法可以方便地制备用作烯丙基[1,2- a ]吲哚和咔唑的正交合成的闭环复分解(RCM)前体的二烯丙基吲哚。该方法的合成效用通过微管蛋白抑制剂和天然存在的咔唑生物碱的合成来说明。
Chiral Naphthyl-C2-Indole as Scaffold for Phosphine Organocatalysis: Application in Asymmetric Formal [4 + 2] Cycloaddition Reactions
作者:Tingting He、Lei Peng、Shan Li、Fangli Hu、Chuandong Xie、Shengli Huang、Shiqi Jia、Wenling Qin、Hailong Yan
DOI:10.1021/acs.orglett.0c02519
日期:2020.9.4
naphthyl-C2-indole bifunctional phosphine organocatalyst in stereoselective formal [4 + 2] cycloadditionreactions were reported. The chiral naphthyl-C2-indole skeleton was introduced to bifunctional phosphine organocatalysis for the first time, and excellent stereocontrol was achieved in two types of formal [4 + 2] cycloadditionreactions. With the optimal catalyst, a series of chiral spirooxindole and hydrodibenzofuran
A convenient and highly α-regioselective strategy for the synthesis of 3-prenyl-3-hydroxy-2-oxindoles has been developed starting from isatins and prenylzinc with good to excellent yields. This protocol provides a straightforward and practical way to introduce an α-prenyl moiety into the C-3 position of isatins. The advantages of this reaction are use of the cheap and readily available reagents, operational
N-Heterocyclic carbene-catalyzed [4 + 2] cyclization of α,β-unsaturated carboxylic acids bearing γ-H with isatins: an enantioselective synthesis of spirocyclic oxindole–dihydropyranones
作者:Ling Zhu、Chenxia Yu、Tuanjie Li、Yuhong Wang、Yinan Lu、Wenjing Wang、Changsheng Yao
DOI:10.1039/c5ob02160j
日期:——
An NHC-catalyzed asymmetric [4 + 2] annulation of isatins and α,β-unsaturated carboxylicacids bearing γ-H gave spirocyclic oxindole–dihydropyranones successfully via an in situactivationstrategy. This protocol featured easy availability of raw materials, good yields and excellent enantioselectivities (up to 99% ee).
Lanthanide amide-catalyzed one-pot functionalization of isatins: synthesis of spiro[cyclopropan-1,3′-oxindoles] and 2-oxoindolin-3-yl phosphates
作者:Cheng Peng、Jiaojiao Zhai、Mingqiang Xue、Fan Xu
DOI:10.1039/c7ob00640c
日期:——
Lanthanide amide-catalyzed one-pot reaction of isatins, dialkyl phosphite, and activated alkenes was developed and a series of spiro[cyclopropan-1,3′-oxindoles] were obtained in moderate to excellent yields. The reaction is stereoselective and the two substituents at the 2 and 3-positions of the cyclopropane in the major product are in the trans configuration. A four-step mechanism involving the Pudovik
access to a broad range of unnatural C2-quaternary 2-hydroxyindoxyls in high yields. The reaction proceeds via a mechanistically intriguing one-pot 1,2-hydride shift followed by autoxidation pathway. The utility of this method is demonstrated by the synthesis of a new class of bis-indoxyl spirofuran derivatives.