Abstract:

 The reaction system (NH₄)₃VS₄/Et₄Br/CuBr/PPh₃ in CH₂Cl₂ for self -assembling of  [VS₄-Cu_n](n from 3 to 6) clusters was simulated in NMR tube. Aft er the  relationship between the \{\}\+\{51\}V NMR chemical shifts and the number of copper atoms in this family cluster was established theoretically and experime ntally, ⁵¹}V NMR was used as a pseudo -in situ- and real-time method to monitor and identify possible prod ucts during the reaction process. The reaction conditions and mechanism about th e formation of [VS₄-Cu_n] clusters were investigated by changing the m olar ratios of the reactants. The results showed that the concentration of PPh₃ has obvious influence on the ⁵¹V chemical shift, and their mechanism is discussed in detail.

Key words: ⁵¹V NMR, Reaction mechanism, V-Cu-S heterometallic cluster, Dynamic process