Process for the preparation of 2,3-Dihydroindoles (indolines), novel 2,3-dihydroindoles, and their use

A process for the preparation of 2,3-dihydroindoles of the formula (I)

• in which the radicals R1 to R7 independently of one another are selected from the group consisting of hydrogen, fluorine, chlorine, (C1-C8)-alkyl, O-alkyl-(C1-C8), OCO-alkyl-(C1-C8), OH, NO2, Si(alkyl)3-(C1-C8), CF3, CN, COOH, CHO, SO3H, NH2, NH-alkyl-(C1-C8), N-alkyl2-(C1-C8), NH—Ar, NAr2, P-alkyl2-(C1-C8), SO2-alkyl-(C1-C6), SO-alkyl-(C1-C6), NHCO-alkyl-(C1-C4), COO-alkyl-(C1-C8), CONH2, CONH-alkyl-(C1-C8), CO-alkyl-(C1-C8), NHCOH, NHCOO-alkyl-(C1-C4), CHCH—CO2-alkyl-(C1-C8), CHCHCO2H, P-alkyl2-(C1-C8), POalkyl2-(C1-C4), PO3H2, PO(O-alkyl-(C1-C6))2, SO3-alkyl-(C1-C4), SO2-alkyl-(C1-C6), SO-alkyl-(C1-C6), Si(alkyl)3-(C1-C8), Ar, O—Ar, CO—Ar, COO—Ar, PO—Ar2 and PAr2;
• where Ar is
• an aromatic radical having up to 14 carbon atoms;
• or
• a heteroaromatic, selected from the group consisting of the five-, six- or seven-membered rings having at least one nitrogen, oxygen and/or sulfur atom in the ring;
• by reaction of halostyrenes of the formula (IIa) or (IIb)
• with amines of the formula (III)
• R1—NH2 (III)
• where in the formulae (IIa), (IIb) and (III)
• R1 to R7 have the same meaning as in formula (I);
• X is selected from the group consisting of chlorine, bromine, iodine, OSO2CF3, OSO2aryl-(C6-C10), OSO2alkyl-(C1-C8) and N2+Y−, where Y is a chlorine, bromine or iodine atom or a tetrafluoroborate or tetraphenylborate anion;
• in at least one inert solvent or in water and in the presence of at least one base, selected from the group consisting of
• primary, seconary and tertiary alkoxides;
• primary and secondary amides of alkali metal and/or alkaline earth metal elements;
• alkyl and aryl compounds of alkali metals and/or alkaline earth metals;
• and
• carbonates, hydroxides, hydrogencarbonates of lithium, sodium, potassium, calcium, magnesium and cesium.