Organometallic compound purification
A method of purifying an organometallic compound by heating the organometallic compound in the presence of a trialkyl aluminum compound and a catalyst.
1. A method of purifying an organometallic compound comprising i) providing a mixture comprising a) an organometallic compound chosen from unsymmetrical dimethyl hydrazine and a compound of the formula R 1 R 2 n−1 M 1 wherein R 1 is chosen from (C 1 -C 20 )alkyl, (C 2 -C 12 )dialkylamino, (C 1 -C 12 )alkylamino(C 1 -C 12 )alkyl, di(C 1 -C 20 )alkylamino(C 1 -C 12 )alkyl, (C 2 -C 20 )alkenyl, (C 2 -C 20 )alkynyl and aryl; each R 2 is independently chosen from hydrogen, (C 1 -C 20 )alkyl, (C 2 -C 12 )dialkylamino, (C 1 -C 12 )alkylamino(C 1 -C 12 )alkyl, di(C 1 -C 20 )alkylamino(C 1 -C 12 )alkyl, (C 2 -C 20 )alkenyl, (C 2 -C 20 )alkynyl, aryl and halogen; M 1 is a Group IIA to Group VIA metal; and n is the valence of M 1 ; and b) a purifying composition comprising an alkyl-metal compound of the formula R 3 x R 4 3-x M 2 wherein R 3 is a (C 1 -C 20 )alkyl; each R 4 is independent chosen from hydrogen and halogen; M 2 is a Group IIIA metal; and x is an integer from 1-3; and a catalyst compound; and ii) heating the mixture.
2. The method of claim 1 wherein the catalyst compound comprises a Group IA, IIA, IIIA or VA metal.
3. The method of claim 2 wherein the catalyst compound further comprises a group chosen from hydrogen, halogen, alkyl, alkenyl, alkynyl, aryl, amino, dialkylamino, aminoalkyl, and dialkylaminoalkyl.
4. The method of claim 1 wherein the catalyst compound is chosen from lithium dimethylamide, tert-butyl lithium, n-butyl lithium, aluminum trichloride, aluminum tribromide, aluminum triiodide, gallium trichloride, indium trichloride, calcium dichloride, barium difluoride, tetramethyl ammonium fluoride, and tris(dimethylamino) aluminum.
5. The method of claim 1 wherein the purifying composition is present in an amount of 0.1 to 10 % wt based on the weight of the organometallic compound.
6. The method of claim 1 wherein the alkyl-metal compound and catalyst compound are present in a weight ratio of 10:1 to 1:10.
7. The method of claim 1 wherein M 2 is aluminum.
8. The method of claim 1 wherein M 1 is chosen from a Group IIIA metal, a Group IVA metal and a Group VA metal.
9. The method of claim 1 wherein the alkyl-metal compound is a Group IIIA trialkyl compound.
10. The method of claim 1 further comprising a step of removing the organometallic compound form the purifying composition.