Two Mn(II)-Bridged Silverton-Type [UMo 12 O 42 ] 8- Polyoxometalates with Catalytic Activity for the Synthesis of Pyrazoles.

Two Mn(II)-bridged Silverton-type {UMo 12 O 42 }-based polyoxomolybdates with different three-dimensional structures, Na 6 (H 2 O) 12 [Mn(UMo 12 O 42 )] ( NaMn ) and (NH 4 ) 2 [K 2 Na 6 (μ 4 -O) 2 (H 2 O) 1.2 Mn(UMo 12 O 42 )]·4.6H 2 O ( KMn ), were hydrothermally synthesized and further characterized, demonstrating a feasible strategy for the assembly of Silverton-type polyoxomolybdates. Additionally, NaMn is demonstrated to be a good heterogeneous catalyst in the condensation cyclization reaction of hydrazines and 1,3-diketones, and a range of valuable pyrazoles were produced in up to 99% yield.