Process for the preparation of platinum acetylacetonato complexes
View Patent ↗Preparation of halogenide-free Platinum(II)acetylacetonate [Pt(acac) 2 ] Platinum(II) hexafluoroacetylacetonate [Pt(hfac) 2 ], Platinum(II) trifluoroacetylacetonate [Pt(tfac) 2 ] or Platinum(II)-alkylsubstituted acetylacetonates by the reaction of a halogen free platinum (IV) oxo- or hydroxo-compound, such as PtO 2 .nH 2 O (n being an integer from 1 to 4) or H 2 Pt(OH) 6 or Na 2 Pt(OH) 6 or K 2 Pt(OH) 6 , with a reducing agent in aqueous solution in the presence of a stoichiometric or higher amount of acetylacetone (acac), potassium acetylacetoante (Kacac) sodium acetylacetonate (Naacac), hexafluoroacetylacetone (hfac), trifluoroacetylacetone (tfac) or alkyl substituted acetylacetones or their salts and an H + donor.
1. A process for the production of halogenide-free
Platinum(II)acetylacetonate [Pt(acac) 2 ] or
Platinum(II) hexafluoroacetylacetonate [Pt(hfac) 2 ] or
Platinum(II) trifluoroacetylacetonate [Pt(tfac) 2 ] or
Platinum(II)-alkylsubstituted acetylacetonate,
wherein
I. a halogen free platinum (IV) oxo- or hydroxo-compound is reacted with
II. a reducing agent
III. in aqueous solution in the presence of
IV. a stoichiometric or higher amount based on platinum (IV) of acetylacetone (acac), hexafluoroacetylacetone (hfac), trifluoroacetylacetone (tfac) or alkyl substituted acetylacetonate or their salts and
V. a H + donor.
2. A process for the production of chloride-free
Platinum(II)acetylacetonate [Pt(acac) 2 ] or
Platinum(II) hexafluoroacetylacetonate [Pt(hfac) 2 ] or
Platinum(II) trifluoroacetylacetonate [Pt(tfac) 2 ] or
Platinum(II)-alkylsubstituted acetylacetonate
according to claim 1 .
3. A process according to claim 1 wherein the halogenide free platinum (IV) oxo- or hydroxo-compound is PtO 2 .n H 2 O or H 2 Pt(OH) 6 ,
n being an integer from 1 to 4.
4. A process according to claim 1 , wherein the reaction temperature is kept under 85° C.
5. A process according to claim 2 , wherein the reaction temperature is kept under 85° C.
6. A process according to claim 1 wherein 30 to 150 molar equivalents of water are present in the reaction mixture.
7. A process according to claim 1 wherein H + is provided by a mineral or organic acid as donor.
8. A process according to claim 7 wherein the mineral acid is one of the following H 2 SO 4 , HNO 3 , and H 3 PO 4 .
9. A process according to claim 1 wherein the reducing agent is selected from the group consisting of formic acid, formic acid derivatives, oxalic acid, hydrazine, hydrazine derivatives, hydrazinium salts, hydrogen peroxide, and alcohols.
10. A process according to claim 9 wherein the reducing agent is used as a dilute aqueous solution.
11. A process according to claim 1 wherein
the product is isolated as a solid precipitate, washed and recrystallized.
12. A process according to claim 11 wherein the product is recrystallized from an organic solvent, optionally in the presence of activated carbon.
13. A process according to claim 1 wherein the reaction is carried out in air.
14. A process according to claim 1 wherein no reagents, which can exacerbate the recovery of Pt from the mother liquors in recycling nor additional metals nor excess organics are present.