93549-88-3Relevant articles and documents
Dearomative Indole (3 + 2) Reactions with Azaoxyallyl Cations - New Method for the Synthesis of Pyrroloindolines
DiPoto, Maria C.,Hughes, Russell P.,Wu, Jimmy
supporting information, p. 14861 - 14864 (2015/12/08)
Herein, we report the first examples of the synthesis of pyrroloindolines by means of (3 + 2) dearomative annulation reactions between 3-substituted indoles and highly reactive azaoxyallyl cations. Computational studies using density functional theory (DFT) (B3LYP-D3/6-311G++) support a stepwise reaction pathway in which initial C-C bond formation takes place at C3 of indole, followed by ring closure to give the observed products. Insights gleaned from these calculations indicate that the solvent, either TFE or HFIP, can stabilize the transition state through H-bonding interactions with oxygen of the azaoxyallyl cation and other relevant intermediates, thereby increasing the rates of these reactions.
The Selective Cross-Coupling of Secondary Alkyl Zinc Reagents to Five-Membered-Ring Heterocycles Using Pd-PEPPSI-IHeptCl
Atwater, Bruce,Chandrasoma, Nalin,Mitchell, David,Rodriguez, Michael J.,Pompeo, Matthew,Froese, Robert D. J.,Organ, Michael G.
supporting information, p. 9502 - 9506 (2015/08/11)
The ability to cross-couple secondary alkyl centers is fraught with a number of problems, including difficult reductive elimination, which often leads to β-hydride elimination. Whereas catalysts have been reported that provide decent selectivity for the expected (non-rearranged) cross-coupled product with aryl or heteroaryl oxidative-addition partners, none have shown reliable selectivity with five-membered-ring heterocycles. In this report, a new, rationally designed catalyst, Pd-PEPPSI-IHeptCl, is demonstrated to be effective in selective cross-coupling reactions with secondary alkyl reagents across an impressive variety of furans, thiophenes, and benzo-fused derivatives (e.g., indoles, benzofurans), in most instances producing clean products with minimal, if any, migratory insertion for the first time. A wide variety of five-membered-ring heterocycles were successfully cross-coupled to secondary alkyl zinc reagents with the new precatalyst Pd-PEPPSI-IHeptCl, which features a bulky N-heterocyclic carbene ligand. This catalyst suppresses migratory-insertion (rearrangement) pathways, and the desired products are thus formed with high selectivity.
Visible light-mediated C-H difluoromethylation of electron-rich heteroarenes
Su, Yi-Ming,Hou, Yu,Yin, Feng,Xu, Yue-Ming,Li, Yan,Zheng, Xiaoqi,Wang, Xi-Sheng
, p. 2958 - 2961 (2014/06/23)
A novel method for visible-light photoredox-catalyzed difluoromethylation of electron-rich N-, O-, and S-containingheteroarenes under mild reaction conditions is developed. Mechanistic investigation indicates that the net C-H difluoromethylation proceeds through an electrophilic radical-type pathway.
Palladium-catalyzed oxidative trifluoromethylation of indoles at room Temperature
Mu, Xin,Chen, Shujun,Zhen, Xingliang,Liu, Guosheng
, p. 6039 - 6042 (2011/06/22)
Incorporation of fluorine atoms into organic molecules significantly enhances many of their properties, such as solubility, metabolic stability, and bioavailability. Among organofluorine molecules, trifluoro ACHTUNGTRENUNGmethylated compounds play a unique and important role in agricultural and medicinal chemistry.[2] As a consequence, the exploitation of efficient methods to construct C-CF3 bond has received much attention.
4-hydroxyphenylthio derivatives, their preparation and their use for the preparation of aminoalkoxyphenylsulphonyl derivatives
-
, (2008/06/13)
The subject of the invention is 4-hydroxyphenylthio derivatives of general formula: STR1 in which: R1 and R2, which are identical or different, each represent hydrogen, a methyl or ethyl radical or a halogen atom, R represents a (Cs
An Expeditious Synthesis of 3-Alkyl-, Aryl- and Heteroaryl-indoles by way of an Intramolecular Horner-Wittig Reaction
Couture, Axel,Deniau, Eric,Gimbert, Yves,Grandclaudon, Pierre
, p. 2463 - 2466 (2007/10/02)
A variety of 3-alkyl-, aryl- and heteroaryl-indoles have been efficiently prepared by base-induced intramolecular cyclization of suitable aromatic o-acyl substituted Horner-Wittig reagents.
Conformational Analysis of 1- and 3-Isopropylindoles. A 1H NMR and Molecular Mechanics Study
Nilsson, Ingemar,Berg, Ulf,Sandstroem, Jan
, p. 491 - 500 (2007/10/02)
The conformations of the isopropyl groups in a series of 1- and 3-isopropylindoles have been studied by 1H NMR and molecular mechanics technique.The isopropyl group is shown to assume both syn and an anti conformation, and the equilibrium between these is shown to depend on the steric size of the substituent in position 2.The syn form is relatively more favoured in the 3- than in the 1-isopropylindoles, which can be explained by differences in the lengths of the ring bonds to N-1 and C-3.The energy barriers to syn-anti exchange are 45-46 kJ mol-1 in the 1-iPr compounds when R2=Me or CO2Me.This barrier is lower in the 3-iPr analogues and could only be measured when R1=iPr, R2=Me (35 kJ mol-1).In the 1-iPr compounds a 3-Me group exerts no observable buttressing effect on a 2-Me group, unlike the situation in 1-iso-propylnaphthalenes, where introduction of a 3-Me group leads to an apparent diminution of the steric effect of the 2-Me group ("negative buttressing").In 1-isopropyl-2-methylindole a 3-Br also exerts a negative buttressing effect.
