DE1768714C - Process for the production of cobalt complex salts - Google Patents

Description

The invention relates to a process for the preparation of cobalt complex salts with a group of the general ones formula

Y '

—N

—N

N -

Co

(D

Y "

N—

in which Y 'and Y "are a Lewis base or an alkyl radical and N - is a nitrogen atom of a chelating agent means less than four oximine groups from compounds of the general formula

—N

N—

Co

(Π)

Ν in which X is a halogen atom, and the by Um

in which X is a haloalom, and that by reaction a cobalt dihalogen in water, alcohol, a ketone or a mixture thereof with a chelating agent with less than four oximine groups in the molecule, thereby gckcnnzeichnct, that the compounds of formula 11 with a slight excess of a Lewis base in an alcohol with Sodium borohydride in the presence of an alkyl halide in an aqueous alcohol or with an Reacts alkyl Grignard Rcagens in an ether. Deposition of a cobalt halide in water, alcohol, a ketone or one (ionic thereof with a chelating agent with fewer than four oximine groups in the Molecule which is characterized in that mao the compounds of the general Formula II with a small excess of one Lewis base in an alcohol with sodium borohydride in the presence of an alk vUialogenids in an aqueous Alcohol odci reacts with an alkyl Grignard reagent in an ether.

From »Chcm. At.". 97, pp. 3056 to 3064 (19641. and “Chcm. Ber. ”, 98. pp. 3324 to 3333 (1965), it is already known that by reaction with sodium boranal and alkyl halide or by reaction with Grignard compounds, alkyl groups on Kobaltatorae can be linked in N-chelal complexes. A process for the preparation of coballchelal complexes is also already known from the first-mentioned reference known by reacting carbon dichloride with a chelating agent.

Of the known cobalt complexes (bis-dimethylglyoxime complexes) differ the cobalt complex obtained by the process according to the invention ». · however, in that the chelating agent has fewer than four oximine groups, while in the known carbon complexes the chelating agents always have four oximine groups. In contrast to the known, water-insoluble, neutral bis-dimelhylglyoxime-cobalt complexes are the cobalt complexes which can be prepared by the process according to the invention, water-soluble kaiionic complexes represent.

From the coball complex salts obtainable by the process according to the invention, organometallic salts can be prepared Derivatives are produced (cf. "Inorg Nucl. Chcm. Letters". P. 561 [1969]). the so far nui produced using tetradentate ligands could (cf. "Chem. Comm", p. 1091 [197O]). With Help of the compounds prepared according to the invention it is possible for the first time by direct transfer of the Methyl group of the organometallic derivative prepared according to the invention on aquocobalamin methylcobalamin to be produced in a new way (cf. "Chem. Comm.", p. 706 [197I]).

The compounds which can be produced according to the invention are, because of their greater resistance, their lower Oxidation state and their solubility in water better catalysts for redox reactions than the bisdimethylglyoxime complexes and other cobalt chelate compounds previously used for this purpose.

According to one embodiment of the invention, the method for the production of cobalt complex salts carried out with a group of the general formula I given above as follows:

If a compound of the general formula II, which is a bi- or trivalent cobalt complex can act, in one of an aqueous alcoholic mixture, for example a water / Methanol mixture with 90% methanol supporting solvent in the presence of an alkyl halide is reacted with sodium borohydride, a compound of the general formula I, in which Y 'and Y "are the same and denote an alkyl radical. An alternative to this process variant is a trivalent cobalt complex of the general formula II with an alkyl Grignard 'reagent in one Ethers, for example tetrahydrofuran, to implement

with formation of an alkylated, water-soluble four-digit Chelate complexes of the trivalciüen cuball.

The compounds of general formula I, tn which Y 'and Y "are equal and cine I £ wisbasc bedeuleo, can be obtained in a simple manner, see chap that a complex of the general formula II mU a slight excess of a Lewis base in Reacts the presence of an alcohol as a solvent. In this implementation, they are preferably used Compounds of general formula II used in which the I lalogcna torn a chlorine, bromine or iodine atom is.

To produce a compound of the general formula in which one of the radicals Y 'and Y "has a Alkyl radical means and the other radical has a meaning other than that of an alkyl radical, becomes one Compound of the general formula II either with sodium borohydride in the presence of an alkyl halide in an aqueous alcohol, for example aqueous methanol, or with an alkyl Grignard agent reacted in an ether as a solvent.

It has already been pointed out that this is in accordance with the invention The chelating agent used must have less than four oximine groups. Preferably one uses such chelating agents. which contain only two oximine groups, e.g. 1,3-bis (diacetylmonoximino) propane. Surprisingly, analogs have chelating agents with four Oximine groups the properties of the crimlative connections that cannot be established. The complex compounds obtainable by the process according to the invention can, as mentioned above, as intermediates in organic syntheses and as catalysts be used in organic reactions.

The invention is illustrated in more detail by the following examples.

example 1
A 10% suspension of

[Co {(DOXDOH) pn! Br ₂ ]

where (DOMDOH) pnl, 3-bis- (diacetylmonoximino) -propane means, in a methyl iodide-saturated methanol-water mixture was reacted with a small excess of sodium borohydride to produce an orange-yellow solution. The methanol was evaporated and the resulting reaction mixture was _{treated with NaClO 4} to produce a crystalline precipitate of

[CH ₃ - Co {(D0KD0H) pn} H ₂ O] C10 ₄

Analysis for C ₁₃ H ₂₆ N ₄ CoO ₇ Cl:

Calculated ... C 33.46, H 5.62, N 13.01%;
found .... C 33.87, HS, 62, N 12.89%.

That used as the starting compound
[Co {(DO) (DOH) pn} Br ₂ ]

was prepared by reacting 7.2 g (30 nmoles) of (D0H) ₂ pn with 9.81 g (30 mmoles) of CoBr ₂ -6H ₂ O. After recrystallization from acetone-water, the desired product was obtained in a yield of 20%.

Example 2

suspended in anhydrous tetrahydrofuran, 2 ^ 5 nmoles of a Melhyl-Grignard solution in tetrahydrofuran were reacted to produce an orange-yellow solution. After hydrolysis, after evaporation of the tetrahydrofuran and treatment with an aqueous NaCK) ₄ solution, the reaction mixture gave a precipitate of

I ₃ - Co «DOKD« H) pn} H ₂ O] CK) ₄

The product was uracrystallized from acetone and water for the production of water-soluble, orange-red crystals of the Foraiel

H ₃ COO CH,

\ I CMi, I / ·

N = C

Co ClO ₄

N = C

/ IH ₂ OI \
HjC CH ₂ CH ₂ CH ₃

/
ClII ₂

40

45

50

55 The starting product used in this example was prepared as described in Example 1 in the same manner.

Example 3

This example illustrates the preparation of a complex in which two molecules of a Lewis base are attached to each Co atom are bound, namely the production of

[Co {(DOKDOH) pnKNH ₃ ) ₂ ] Br ₂

1.15 g (2.5 mmol) of as described in Example 1, manufactured

[Co {(DO) (DOH) pn} Br ₂ ]

suspended in 50 ml of ethanol were _{reacted with a gaseous stream of NH 3} until the starting material had completely disappeared. A yellow precipitate was obtained and filtered off. This solid was recrystallized by dissolving it in a minimal amount of water and precipitating with acetone. The yellow crystals obtained were analyzed.

Analysis:

Calculated ... C 26.85, H 5.12, N 17.80%;
found .... C 27.08, H 5.05, N 16.88%.

Claims (1)

Claim: Process for the production of coballkotnplex salts with a group c? -r general Ϊ * X -NiN- Cxi N y N
Y " in which Y 'and Y "are a Lewis base or an alkyl radical and N- a nitrogen atom of a chelating agent; with less than four oximine groups means from compounds of the general formula N! N
l Co (H) N-