Transition Metal Complexes of the Lacunary Heteropolytungstate

TRANSITION METAL COMPLEXES OF THE LACUNARY HETEROPOLYTUNGSTATE, [PaWnOn] - 

Submitted by WILLIAM J. RANDALL, DAVID K. LYON,n PETER J. DOMAILLE, and RICHARD G. FINKE  

The synthesis and characterization of isolated, isomerically pure a2-[P2W17061(Mn+ L)]y- (Mn+ = Mn3 +, Fe3+, Co2+, Ni2+, and Cu2+) as aqueous-soluble potassium salts (L = HzO) and as the more novel, organic-solvent-soluble tetrabutylammonium salts (L = Br) are described herein. These preparations yield mono-metal-substituted complexes of the Dawson 2 isomer, 2-[P2Wi7O6i]10, that are typically 98% free of the (Xi isomer.1,2 The X-ray crystallographic structures of the a2-[P2W17O61]10 lacunary precursor and the a2-[P2W17061(Co OH2)]8- complex are known.3 

5 Central Research Development, The DuPont Company, Experimental Station, Wilmington, DE 19898. 

The IR spectrum (KBr pellet) is the simplest way to identify these complexes. It is essential that the spectrum for each complex exactly match to ensure purity. For this reason, the IR spectra for these complexes are included.12 

DECAPOTASSIUM Oj-TRIPENTACONTAOXOBIS-[PHOSPHATO(3-)]HEPTADECATUNGSTATE(10-) PENTADECAHYDRATE, K,o[ 2-P2W 0 ] ISHjO 

The PNMR in 1 1 H20 D20 at 20°C of the Li salt (in order to increase the solubility of the anion, the K is replaced by Li by metathesis of 1-2 g of sample with 1-2 g of LiClO in 6-10 mL of 1 1 H20 D20 followed by cooling to 2-3°C and gravity filtration through Whatman or No. 5 filter paper to remove the solid KCIO4) indicates the product is greater than 98% pure a2-[P2Wi706i] ° vvith peaks at —7.27, — 14.11 ppm (relative to 85% H3PO4 at 22 1°C by the substitution method). Confirmation that the preparation yields the 2 isomer (and not the isomer) was obtained by 

HEPTAPOTASSIUM Oj-[AQUAMANGANATE(ni)]-TRIPENTACONTAOXOBIS[PHOSPHO(3-)] HEPTADECATUNGSTATE(7-)TRIDECAHYDRATE, 

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