A novel method for Lewis acid catalyzed Nenitzescu indole syntheses of 5‐hydroxyindoles bearing different substituents in positions 1 )Alk, Bn, Ar), 2 )Me, Et, Ph), and 3 )COOEt, COMe, CONHPh) as well as tricyclic derivatives are reported. The method is simple, rapid, efficient, and allows preparation of hydroxyindoles from 1,4‐benzoquinone and enamines in good to excellent yields with the use of low‐polar solvents in the presence of weak Lewis acids catalysts. The formation of 5‐hydroxyindoles under such mild conditions is explained in terms of a non‐redox mechanism.

Indole derivatives R 0140Lewis Acid Catalyzed Nenitzescu Indole Synthesis. -This simple, rapid, and efficient method enables the preparation of hydroxyindoles like (III) from benzoquinone (I) and enamines (II) in good to excellent yields in the presence of weak Lewis acid catalysts using low-polar solvents. The experimental conditions for the realization of the Nenitzescu reaction are defined via a non-redox mechanism. -(VELEZHEVA*, V. S.; KORNIENKO, A. G.; TOPILIN, S. V.; TURASHEV, A. D.; PEREGUDOV, A. S.; BRENNAN, P. J.; J. Heterocycl. Chem. 43 (2006) 4, 873-879; Nesmeyanov Inst. Organoelem. Compd., Russ. Acad. Sci., Moscow 119991, Russia; Eng.) -H. Hoennerscheid 52-120

No abstract

Molecular masses of the complexes that form upon the reaction of (2 p Tolylindenyl) 2 ZrMe 2 with Al in toluene at room temperature were determined by means of electrospray mass spectrometry. It was determined that zirconium is arranged between two dimeric clusters with the monozirconium cation (L 2 ZrBu i+ ⋅ HAl ) 2 and dizirconium cation {[L 2 ZrBu i (µ CH 3 )Bu i ZrL 2 ] + ⋅ HAl } 2 in these complexes.