Method for making organometallic compounds
Organometallic compounds of Group IIB and IIIA metals that are substantially pure and contain low levels of oxygenated impurities are provided. Also provided are methods of preparing such organometallic compounds.
1. A method of preparing an organometallic compound comprising the steps of: reacting a compound of the formula R 1 a′ M1 b′ Y 1 c′ wherein each R 1 is independently a (C 1 –C 10 ) organic radical, M1 is a Group IIB or IIIA metal, each Y 1 is independently a (C 1 –C 4 ) carboxylate or halogen, a′=0–2, b′ is the valence of M1, c′=1–3, and a′+c′=b′, with a compound of the formula R 2 x M2Y 2 3-x wherein each R 2 is independently a (C 1 –C 10 ) organic radical, M2 is a Group IIIA metal, each Y 2 is independently a (C 1 –C 4 ) carboxylate or halogen, x=1–3, in the presence of a tertiary amine, a tertiary phosphine or a mixture of a tertiary amine and a tertiary phosphine, wherein an electronegativity of M1≧ an electronegativity of M2.
2. The method of claim 1 wherein Y is halogen.
3. The method of claim 1 wherein the reaction is performed in the presence of an organic solvent.
4. The method of claim 3 wherein M1 and M2 are both aluminum.
5. The method of claim 1 further comprising a heating step.
6. The method of claim 1 wherein each R 1 and each R 2 are (C 1 –C 6 )alkyl.
7. The method of claim 1 wherein the tertiary amine has a formula NR 4 R 5 R 6, wherein R 4, R 5 and R 6 are independently chosen from (C 1 –C 6 )alkyl, di(C 1 –C 6 )alkylamino-substituted (C 1 –C 6 )alkyl, and phenyl; and wherein R 4 and R 5 may be taken together along with the nitrogen to which they are attached to form a 5–7 membered heterocyclic ring.
8. The method of claim 7 wherein a trialkyl aluminum and an aluminum trihalide are produced.
9. The method of claim 1 wherein the organometallic compound has the formula R a M b Y c , wherein each R is independently a (C 1 –C 10 ) organic radical, M=M1, Y=Y 1 , a=1–3, b is the valence of M, c=0–2, and a+c=b.
10. The method of claim 9 wherein M is indium, gallium or aluminum.
11. The method of claim 9 , wherein M is a Group IIIA metal, Y=halogen and c ≠0, and further comprising the step of contacting the organometallic compound with a reducing agent in an organic solvent, optionally in the presence of a tertiary amine, a tertiary phosphine or a mixture of a tertiary amine and a tertiary phosphine, to provide a Group IIIA metal hydride compound.
12. The method of claim 1 wherein the tertiary phosphine has the formula R 7 R 8 R 9 P, where R 7 , R 8 , and R 9 are independently chosen from (C 1 –C 6 )alkyl, phenyl and (C 1 –C 6 )alkyl-substituted phenyl.
13. A method of preparing an organometallic compound comprising the steps of: reacting a compound of the formula R 1 a′ M1 b′ Y 1 c′ wherein each R 1 is independently a (C 1 –C 10 ) organic radical, M1 is a Group IIB or IIIA metal, each Y 1 is independently a (C 1 –C 4 ) carboxylate or halogen, a′=0–2, b′ is the valence of M1, c′=1–3, and a′+c′=b′, with a compound of the formula R 2 x M2Y 2 3-x wherein each R 2 is independently a (C 1 –C 10 ) organic radical, M2 is a Group IIIA metal, each Y 2 is independently a (C 1 –C 4 ) carboxylate or halogen, and x=1–3, in the presence of a tertiary amine, a tertiary phosphine or a mixture of a tertiary amine and a tertiary phosphine, wherein an electronegativity of M1≧ an electronegativity of M2; wherein the organometallic compound has the formula R a M b Y c , wherein each R is independently a (C 1 –C 10 ) organic radical, M=M1, Y=Y 1 , a=1–3, b is the valence of M, c=0–2, and a+c=b; and wherein the organometallic compound has ≦0.5 ppm of metallic impurities chosen from silicon, germanium and tin.
14. The method of claim 13 wherein the reaction is performed in the presence of an organic solvent.
15. The method of claim 13 further comprising a heating step.