Microwave methods for the synthesis of paddlewheel diruthenium compounds with N,N-donor ligands

Microwave irradiation can lead to easy and fast synthesis methods in the obtention of paddlewheel diruthenium complexes with N,N-donor ligands. Microwave assisted substitution of acetate groups on [Ru2Cl(O2CMe)4] by three different types of N,N-donor ligands gives rise to [Ru2(DPhT)4] (1), (DPhT- = 1,3-diphenyltriazenide); [Ru2(DFPhT)4] (2), (DFPhT- = 1,3-bis(p-fluorophenyl)triazenide); [Ru2Cl(DPhF)4] (3), (DPhF- = 1,3-diphenylformamidinate); [Ru2Cl(DAniF)4] (4), (DAniF- = 1,3-bis(p-methoxyphenyl)formamidinate); and [Ru2Cl2(hpp)4] (5), (hpp- = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-[small alpha]]pyrimidinate). In addition, the selective replacement of the acetate group on [Ru2Cl(DPhF)3(O2CMe)] by [1,3,5-(O2C)3C6H3]3- under microwave irradiation produces {[Ru2Cl(DPhF)3]3(O2C)3C6H3}[middle dot]3H2O, (6). The experimental conditions have been optimised in every case to obtain better yields and more environmentally friendly reaction conditions than the ones reported by other conventional methods of synthesis.