Process for preparing trialkylgallium compounds

US9108985B2 · kind B2 · utility

Assignee

• UMICORE AG & CO. KG · DE

Inventors

• Ralf Karch · Kleinostheim, DE
• Andreas Rivas-Nass · Schriesheim, DE
• Annika Frey · Hanau, DE
• Tobias Burkert · Murr, DE
• Eileen Woerner · Nidderau, DE
• Angelino Doppiu · Seligenstadt, DE

Key dates

• Filing date: Nov 28, 2012
• Grant date: Aug 18, 2015
• Expiry date: Nov 28, 2032

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/582
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

The invention relates to a process for preparing trialkylgallium compounds of the general formula R3Ga. The process is based on the reaction of gallium trichloride (GaCh), optionally in a mixture with partially alkylated products, with an alkylaluminium compound of the type RaAICIb (where R═C1-C5-alkyl, a=1, 2 or 3, b=0, 1 or 2 and a+b=3) in the presence of at least two alkali metal halides (e.g. NaCI and KCI) as auxiliary base. Preference is given to using alkylaluminium sesquichloride (R3AI2CI3) or trialkylaluminium (R3AI). The reaction mixture is heated to a temperature in the range from 120° C. to 250° C. and the trialkylgallium compound formed is separated off via a separator which is operated at a temperature which is more than 30° C. below the boiling point of the most volatile partially alkylated product. Complete alkylation is achieved here and partially alkylated products are recirculated to the reaction mixture. In a further step, the reaction mixture can be heated to a maximum of 350° C. and the remaining fully alkylated and partially alkylated products can be separated off. The process provides a high yield of trialkylgallium compound and displays high gallium utilizat…