ORGANOMETALLIC COMPOUNDS

Abstract

The present patent application relates to novel allyl cobalt complexes, to a process for their preparation and to their use for vapor deposition.

Claims

1.-18. (canceled)

19. A method for the preparation of allyl-cobalt complexes having the general formula [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] or [Co(η.sup.3-allyl-R1)(CO).sub.3] comprising the steps of a) reacting cobalt octacarbonyl Co.sub.2(CO).sub.8 with a trialkylhydrosilane of the form (R2).sub.3Si—H to a cobalt complex having the general formula [(R2).sub.3Si—Co(CO).sub.4]; b) reacting the resulting cobalt complex having the general formula [(R2).sub.3Si—Co(CO).sub.4] with an organic ester having the general formula R3-(CO.sub.2-Allyl-R1) where X=1, 2 or 3, to cobalt complex [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3], wherein R1 and R2 are independently hydrogen or alkyl and R3 is alkyl, cycloalkyl or aryl.

20. The method according to claim 19, wherein R1 is selected from the group consisting of H, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclobutyl and combinations thereof.

21. The method according to claim 19, wherein R2 is selected from the group consisting of H, methyl, ethyl, n-propyl, isopropyl, n-butyl, and combinations thereof.

22. The method according to claim 19, wherein R3 is a C3 to C10 alkyl, cycloalkyl or aryl, which may be substituted or condensed with a C1 to C8 alkyl or cycloalkyl.

23. The method according to claim 19, wherein R3 is selected from hexyl, heptyl, octyl, cyclohexyl, cyclooctyl, phenyl, 2-cyclohexylethyl or combinations thereof.

24. The method according to claim 19, wherein the organic ester having the general formula R3-(CO.sub.2-allyl-R1).sub.x is a heptanoate of the C.sub.6H.sub.13CO.sub.2-allyl-R1 type.

25. The method according to claim 19, wherein in step b) a solvent is used which has a boiling point of more than 200° C. at atmospheric pressure.

26. The method according to claim 19, wherein the organic ester having the general formula R3-(CO.sub.2-allyl-R1).sub.x or squalane is used as the solvent having a boiling point of more than 200° C. at atmospheric pressure.

27. The method according to claim 19, wherein the reaction temperature in step a) is between 20° C. and 55° C., or between 25° C. and 30° C.

28. The method according to claim 19, wherein in step a) branched or unbranched alkanes, ethers or aromatics having 5 to 10 carbon atoms are used as the solvent.

29. The method according to claim 19, wherein the solvent used in step a) is pentane, hexane, heptane, octane, benzene, toluene, diethyl ether, diisopropyl ether, tetrahydrofuran, dioxane or combinations thereof.

30. The method according to claim 19, wherein the cobalt complex [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] is produced in a single pot method.

31. The method according to claim 19, wherein the cobalt complex [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] is produced in a single pot method, a solvent is used in step a) and this is removed before carrying out step b).

32. The method according to claim 19, further comprising a step c), wherein in step c) the cobalt complex [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] is removed from the reaction mixture.

33. The method according to claim 19, further comprising a step c), wherein in step c) the cobalt complex [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] is removed from the reaction mixture by distillation.

34. A method for the vapor deposition of cobalt-containing layers comprising the steps of providing allyl-cobalt complexes having the general formula [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] or [Co(η.sup.3-allyl-R1)(CO).sub.3] according to claim 19; employing the allyl-cobalt complexes having the general formula [Co(η.sup.3-C.sub.3H.sub.4—R1)(CO).sub.3] or [Co(η.sup.3-allyl-R1)(CO).sub.3] in a method for vapor deposition of cobalt-containing layers.

35. The method according to claim 34, wherein the deposition is by thermal decomposition.

36. The method according to claim 34, wherein said method is an ALD (Atomic Layer Deposition) or CVD (Chemical Vapor Deposition) method.

Description

EXAMPLES

Example 1

Step a.: Reaction of Dicobalt Octacarbonyl with Triethylsilane to Triethylsilyl Cobalt Tetracarbonyl

[0028] In a 4 liter 4 neck glass flask equipped with a KPG stirrer, a temperature sensor for controlling the internal temperature, a dropping funnel without gas compensation and an intensive cooler with a pressure relief valve, 638 g of dicobalt octacarbonyl (1.86 mol, 1.00 eq.) are introduced and slurried with 1.00 liter of heptane. The reaction flask is maintained at 20±4° C. by means of a water bath. The reaction mixture is stirred at 300 rpm. This is followed by dropwise addition of 467 g of triethylsilane (4.02 mol, 2.15 eq.) over the course of four hours, in which case it is ensured that the internal temperature is in the range of 20±4° C. After the end of the addition, the triethylsilane container is rinsed with 100 mL of heptane and the heptane/triethylsilane mixture is added to the reaction mixture. The reaction mixture is stirred at room temperature overnight. The next day, the heptane solvent and excess triethylsilane are distilled off from the reaction mixture at 50° C. internal temperature and a pressure of 30 mbar. When the distillate stream begins to run dry, the pressure is successively reduced to a final pressure of 18 mbar. The product remains in the reaction flask. Isolated: 1095 g.

[0029] The product can be subjected to a purification step:

[0030] For this purpose, the product is condensed in dynamic vacuum. The internal temperature is 50° C., the condenser is cooled with 0° C., and the vacuum is <1*10.sup.−3 mbar. 573 g of crude product thus yield 534 g of purified material.

Example 2

Step b.: Reaction of Triethylsilyl Cobalt Tetracarbonyl with Allyl Heptanoate to [Co(η.SUP.3.-C.SUB.3.H.SUB.5.)(CO).SUB.3.]

[0031] 400 g of purified triethylsilyl cobalt tetracarbonyl (1.40 mol, 1.00 eq.) is introduced into a 4 liter 4-neck glass flask equipped with magnetic stirring core, an intensive cooler with a pressure relief valve, a dropping funnel without gas compensation, a temperature sensor for controlling the internal temperature and a distillation column in combination with a distillation bridge and a condenser. The system can be rendered inert and also evacuated via the condenser. The intensive cooler and the distillation bridge are cooled to −10° C. For the first part of the reaction, the released gas is discharged via the intensive cooler with pressure relief valve. The reaction mixture is stirred at 300 rpm, heated to 70° C. internal temperature, and at this temperature 263 g of allyl heptanoate (1.54 mol, 1.10 eq.) are added dropwise. This takes place within 70 minutes, in which case the dropping rate is adjusted in such a way that the internal temperature remains at 70±5° C. After the end of the addition, the reaction mixture is stirred for a further three hours at 70° C. until no further evolution of gas is observed. The second part of the reaction consists of distillation of the crude product. The condenser is cooled to about −40° C. and, with stirring at 300 rpm, vacuum is slowly applied to the apparatus via the condenser at a sump temperature of 70° C. At a pressure of 29 mbar, the product begins to distill. When the distillate stream tends to sediment, the pressure is successively reduced to 7 mbar. This yields 236 g of the crude product (1.29 mol, 92%) with a purity of 99 m %.

[0032] The crude product can be purified by fine distillation:

[0033] Distillation at an internal temperature of 40° C. and a pressure of 10 mbar via a Vigreux column yields 92% of a product which has a purity of >99 m % of [Co(η.sup.3-C.sub.3H.sub.5)(CO).sub.3].

Example 3

Step b.: Reaction of Triethylsilyl Cobalt Tetracarbonyl with Diallyl Phthalate to [Co(η.SUP.3.-C.SUB.3.H.SUB.5.)(CO).SUB.3.]

[0034] 100 g of purified triethylsilyl cobalt tetracarbonyl (0.35 mol, 1.00 eq.) were introduced into a 500 ml 4-neck glass flask equipped with magnetic stirring core, an intensive cooler with a pressure relief valve, a dropping funnel with gas compensation, a temperature sensor for controlling the internal temperature and a distillation bridge with a receiver. The system may be evacuated and inertized. The distillation bridge was cooled to −25° C. The triethylsilyl cobalt tetracarbonyl was stirred at 300 rpm, heated to 70° C. internal temperature and at this temperature 47.8 g of diallyl phthalate (0.19 mol, 0.55 eq.) were added dropwise. This addition was taking place within 70 minutes and the dropping rate was adapted in such a way that the internal temperature was at 70±5° C. After the addition, the reaction mixture was further stirred at 70° C. internal temperature for three more hours until no more gas evolution could be observed.

[0035] The second part of the reaction was consisting of the distillation of the raw product. The receiver was cooled to about −40° C. and while stirring the reaction mixture at 300 rpm at a temperature of 70° C., the apparatus was slowly evacuated via the receiver. At a pressure of 30 millibar the product started to distill. When the flow of distillate was about to run dry, the pressure was further reduced successively to a final pressure of 10 millibar. 60.3 g of raw product (0.33 mol, 94%) with a purity of >99% were obtained.