[VS_4-Cu_n](n=3-6)簇合物成簇反应的~(51)V NMR研究 ; ~(51)V NMR STUDIES ON THE REACTION OF [VS_4-Cu_n] (n=3-6) CLUSTERS

在核磁管内模拟反应体系 (NH4)3VS4/Et4NBr/CuBr/PPh3在CH2 Cl2 溶液中生成[VS4 Cun](n =3 6 )簇合物的过程 .利用 51 VNMR技术对反应过程进行准原位的实时监测 ,研究 [VS4 Cun](n =3 6 )簇合物的成簇条件和机理以及配体对成簇过程的影响 .本文还详细讨论了反应溶液中不同浓度的PPh3对 [VS4 Cu4]簇合物的51 VNMR化学位移的影响 . The reaction system (NH4 ) 3VS4/ Et4NBr/ CuBr/ PPh3 in CH2Cl2 for self2assembling of [VS 4-Cu n ] ( n from 3 to 6)clusters was simulated in NMR tube. After the relationship between the 51V NMR chemical shift s and the number of copper atoms in this family cluster was established theoretically and experimentally , 51V NMR was used as a pseudo in sit u and real2time method to monitor and identify possible product s during the reaction process. The reaction conditions and mechanism about the formation of [VS4 2Cu n ] clusters were investi2 gated by changing the molar ratios of the reactant s. The result s showed that the concentration of PPh3 has obvious influence on the 51V chemical shift , and their mechanism is discussed in detail. ; 国家自然科学基金重点资助项目 (No.2 9832 0 2 0 ) ; 福建省自然科学基金资助项目 (No .C991 0 0 0 1 )