Synthesis of Cu(I) octamolybdates using tetrakis-acetonitrilecopper(I) hexafluorophosphate

Abstract

Reaction of (NBu 4) 2[Mo 2O 7] with [Cu(CH 3CN) 4](PF 6) in acetonitrile results in isolation of the orange β-octamolybdate [Cu(CH 3CN) 4] 2[Mo 8O 26Cu 2(CH 3CN) 4] ( 1) along with the colourless α-octamolybdate [Cu(CH 3CN) 4] 4[Mo 8O 26]·2CH 3CN ( 2). Both products decompose rapidly upon removal from their mother liquors, forming an insoluble, dark brown coloured phase with the composition Cu 4[Mo 8O 26]·0.6CH 3CN·16H 2O ( 3). The copper(I) acetonitrile derivatised isopolyanion in 1 thus represents an intermediate structure between the simple, underivatised octamolybdate 2 and fully condensed, polymeric phase 3.