Method for producing alkyl-indium compounds and the use thereof

Process for preparing a compound (C) having the general formula:

• R2INR'
• comprising the following additional reaction steps:
• c1) separating dialkylinditun chloride from compound (A), where the dialkylindium chloride satisfies the general formula:
• R2InCl
• where R is as defined above;
• and
• c2) reacting R2InCl with an alkylating aunt to form compound (C)
• where R is a nucleophilic radical selected from the group consisting of branched or branched and substituted or unsubstituted alkyl, branched or unbranched and substituted or unsubstituted aryl, which may especially be substituted by branched or unbranched alkyl or alkoxy groups or by amine radicals.

A process according to claim1 4 for preparing trialkylindium of the formula R3In where R is an alkyl radical having 1 to 4 carbon atoms, the alkyl radical may be branched or unbranched and may especially be ethyl or methyl, comprising the steps of

• preparing a compound (A) of the formula R3In2Cl3 by reacting indium metal with an alkyl chloride of the formula RCl in the presence of an activator;
• optionally isolating the compound (A);
• reacting the compound (A) with an alkyllithium to form lithium tetraalkylindate LiInR1, and isolating and optionally further purifying it;
• reacting the lithium tetraalkylindate LiInR4 with an indium chloride compound to give the trialkylindium of the formula R3In;
• where
• in the preparation of compound (A) 1.5 to 3 equivalents, especially 1.5 to 2.5 equivalents, of alkyl chloride per equivalent of indium are used.