The photolysis of MCpâ²(CO)4 (Cpâ²Â = Cp or indenyl; M = Nb or Ta) in polyethylene (PE) matrices at low temperature under a high pressure of reactant gas led to formation of a wide range of photoproducts. Under an inert atmosphere (helium), NbCpâ²(CO)3 and NbCpâ²(CO)2 are observed following irradiation of the parent tetracarbonyl. However, only TaCpâ²(CO)3 is observed for the analogous reactions of the corresponding tantalum compounds. Similarly, NbCpâ²(CO)3(N2) and NbCpâ²(CO)2(N2)2 are seen following irradiation of NbCpâ²(CO)4 under a high pressure of N2, whereas only TaCpâ²(CO)3(N2) was observed following irradiation of TaCpâ²(CO)4. Under hydrogen, the classical dihydride TaCpâ²(CO)3H2 is formed following irradiation of TaCpâ²(CO)4. The non-classical dihydrogen complex Nb(C9H7)(CO)3(η2-H2) is formed following irradiation of Nb(C9H7)(CO)4. NbCp(CO)4 forms both the classical hydride and non-classical dihydrogen complex. Using a high pressure-low temperature cell, the thermal reaction of TaCpâ²(CO)3(N2) with hydrogen to form TaCpâ²(CO)3H2 was observed. Preliminary room temperature studies suggest that Ta(C9H7)(CO)3H2 is ca. 50 times more reactive than TaCp(CO)3H2 in PE.
在低温下,在高压反应气体环境中,MCp²(CO)4(Cp² = Cp 或 indenyl;M = Nb 或 Ta)在聚
乙烯(PE)基体中的光解反应导致形成广泛的光产物。在惰性气氛(
氦气)下,母体四羰基的辐照后观察到 NbCp²(CO)3 和 NbCp²(CO)2。然而,对于相应的
钽化合物的类似反应中,仅观察到 TaCp²(CO)3。类似地,在高压氮气环境下,辐照 NbCp²(CO)4 后观察到 NbCp²(CO)3(N2) 和 NbCp²(CO)2(N2)2,而辐照 TaCp²(CO)4 后仅观察到 TaCp²(CO)3(N2)。在
氢气气氛下,辐照 TaCp²(CO)4 后形成经典的二
氢化物 TaCp²(CO)3H2。辐照 Nb(
C9H7)(CO)4 后形成非经典的二氢复合物 Nb( )(CO)3(η²-H2)。NbCp(CO)4 形成经典
氢化物和非经典二氢复合物。利用高压低温反应池,观察到 TaCp²(CO)3(N2) 与
氢气的热反应生成 TaCp²(CO)3H2。初步的室温研究表明,Ta( )(CO)3H2 的反应性约为 TaCp(CO)3H2 在聚
乙烯中高出约 50 倍。