New pronounced progress in the synthesis of group 5 polyoxometalates†
The chemistry of polyoxomolybdates and polyoxotungstates has been systematically developed since their first discovery more than 100 years ago. In contrast, significant progress in the related chemistries of polyoxovanadates, polyoxoniobates and polyoxotantalates was mainly made during the last few years. This highlight summarizes new synthetic approaches for the generation of high-nuclearity group 5 polyoxometalates and discusses the synthetic conditions influencing product formation. The application of new precursors allows rational syntheses of group 5 polyoxometalates. The importance of the knowledge of the species in liquid media is also discussed and results of in situ investigations are presented.