A convenient access to 1,3-disubstituted furo[3,4-b]indoles by acid ion-exchange resin-catalyzed furan formation
摘要:
Efficient synthesis of furo[3,4-b]indoles starting from the corresponding indole is reported. The first route involves derivatization, protection, and deprotection steps, which stretch the syntheses. The second method provides a shorter and more efficient strategy to accessing the furoindole. The innovation starts with alkylation at C-2 of the indole presenting at the C-3 position a ketone-acetal, followed by the cycloaromatization catalyzed by polymeric ion-exchange resins. The second route represents a significant improvement over other methods previously described. (C) 2011 Elsevier Ltd. All rights reserved.
A consecutive 2-step synthesis of N-unprotected polysubstituted indoles bearing an electron-withdrawing group at the C-3 position from readily available nitroarenes is reported. The protocol is based on the [3,3]-sigmatropic rearrangement of N-oxyenamines generated by the DABCO-catalyzed reaction of N-arylhydroxylamines and conjugated terminal alkynes, and delivers indoles endowed with a wide array
3-Acylindoles via a One-Pot, Regioselective Friedel-Crafts Reaction
作者:Wayne M. Stalick、James H. Wynne、Christopher T. Lloyd、Samuel D. Jensen、Sean Boson
DOI:10.1055/s-2004-831177
日期:——
Within we report a general one-pot high-yielding Friedel-Crafts acylation of indole using acid chlorides and diethyl- aluminum chloride in gram scale quantities. This general synthesis affords products that are easily isolated and require no complex pu- rification procedures.
A weak carbonyl coordination-guided regioselective C4 allylation of indoles is demonstrated using the versatile Morita-Baylis-Hillman adduct in the presence of Rh catalysts in a redox-neutral fashion. The substrate scope, functional group diversity, oxidant free character, mechanistic aspects, and synthetic utilities are important practical features.
coordination facilitated tunable reactivity between alkenylation and alkylation of indoles at the C4 C-H site is presented using readily accessible allylic alcohols in the presence of Rh catalysis by switching the additives or directing group. Exclusive site selectivity, functional group tolerance, and late-stage modifications are the important practical features.
Insecticidal activity of indole derivatives against Plutella xylostella and selectivity to four non-target organisms
作者:Ângela C. F. Costa、Sócrates C. H. Cavalcanti、Alisson S. Santana、Ana P. S. Lima、Thaysnara B. Brito、Rafael R. B. Oliveira、Nathália A. Macêdo、Paulo F. Cristaldo、Ana Paula A. Araújo、Leandro Bacci
DOI:10.1007/s10646-019-02095-1
日期:2019.10
have resistance to a range of insecticides. Indole derivates can exert diverse biological activities, and different effects may be obtained from small differences in their molecular structures. Indole is the parent substance of a large number of synthetic and natural compounds, such as plant and animal hormones. In the present study, we evaluate the insecticidalactivity of 20 new synthesized indole