{2-[Bis(3-methyl-1H-indol-2-yl)methyl]phenolato-κO}dimethyl(tetrahydrofuran-κO)aluminium(III)

Abstract

The title compound, [Al(CH3)2(C25H21N2O)(C4H8O)], was isolated as a minor component from a reaction mixture of the parent indolyl ligand and trimethyl­aluminum in tetra­hydro­furan. The ligands adopt a distorted tetra­hedral geometry around aluminium. Obvious hydrogen-bonding interactions are not present.

Magnetic Aerogels for Room-Temperature Catalytic Production of Bis(indolyl)methane Derivatives

“…Mineral acids (such as HCl, HBr, or H 2 SO 4 ) and organic acids (such as formic or acetic acids [29][30][31][32], sulfamic acid [33][34][35][36], or p-Toluenesulfonic acid [37]) have been successfully employed as catalysts in this method. Furthermore, tests of a wide selection of Lewis acids (such as chlorides, oxides, and other salts of transition metals such as Fe, Cu [38][39][40][41][42], Zn [43,44], Al [45,46], Ti [47][48][49], and Zr [50], along with different examples of rare earth salts) have been reported in the literature. Among other examples, Wang and co-workers studied with an extensive screening the effect of the nature of the Lewis acids used as catalytic species in the reaction between indole and benzaldehyde [51].…”

“…Mineral acids (such as HCl, HBr, or H2SO4) and organic acids (such as formic or acetic acids[29][30][31][32], sulfamic acid[33][34][35][36], or p-Toluenesulfonic acid[37]) have been successfully employed as catalysts in this method. Furthermore, tests of a wide selection of Lewis acids (such as chlorides, oxides, and other salts of transition metals such as Fe, Cu[38][39][40][41][42], Zn[43,44], Al[45,46], Ti[47][48][49], and Zr[50], along with different examples of rare earth salts) have been reported in the literature. Among other examples, Wang and co-workers studied with an extensive screening the effect of the nature of the Lewis acids used as catalytic species in the reaction between indole and benzaldehyde[51].As an alternative to the synthesis under homogeneous catalysis, different approaches based on heterogeneous catalysis have been proposed, including those based on HY and ZnY zeolites[52][53][54], polystyrene-based resins[55], amberlyst[56][57][58], PEG-supported sulfonic acid[59], lanthanide resins[60], and montmorillonite clay K-10 catalysts[61].Nanocrystalline catalysts such as semiconducting CdS nanorods have also been proposed for the synthesis of bis(indolyl)methanes in different media at reflux temperature[62], opening the way to greener approaches such as solvent-free reaction at 80 °C mediated by magnetically recoverable γ-Fe2O3 nanocatalysts[63].…”

Synthesis and crystal structures of some bis(3-methyl-1H-indol-2-yl)(salicyl)methanes

“…There is a significant number of polyindolylmethane crystal structures in the literature where these compounds are ligated to metal atoms or main-group elements through the N atoms (vide supra) or pendant heteroatoms (Eisenberg et al, 2009), but there are few reports of the free molecules themselves (Mason, Barnard et al, 2003;Mason, 2003), which is the focus of this report.…”