Synthesis and reactivity studies of the diphosphine ligand 2-(ferrocenylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (fbpcd): Bridge-to-chelate ligand isomerization kinetics in Os3(CO)10(fbpcd) and X-ray diffraction structure of the ortho-metalated cluster HOs3(CO)9[μ-PhP(C6H4)CC(PPh2)C(O)CCH(C5H4FeCp)C(O)]
作者:William H. Watson、Bhaskar Poola、Michael G. Richmond
DOI:10.1016/j.poly.2007.03.057
日期:2007.8
of ferrocenecarboxaldehyde with 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) yields the new diphosphine ligand 2-(ferrocenylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (fbpcd) in near quantitative yield. The reaction of fbpcd with the activated cluster 1,2-Os3(CO)10(MeCN)2 has been examined, with the diphosphine-bridged cluster 1,2-Os3(CO)10(fbpcd) (2b) observed as the major
摘要二茂铁甲醛与4,5-双(二苯基膦基)-4-环戊烯-1,3-二酮(bpcd)的Knoevenagel缩合反应生成新的二膦配体2-(二茂铁亚基)-4,5-双(二苯基膦基)-4-环戊烯-1,3-dione(fbpcd)的定量产量接近。已经研究了fbpcd与活化簇1,2-Os3(CO)10(MeCN)2的反应,其中以二膦桥联簇1,2-Os3(CO)10(fbpcd)(2b)为主要反应产品。团簇2b是不稳定的,并且在加热时转变成相应的螯合异构体1,1-Os3(CO)10(fbpcd)(2c)。通过1H NMR和UV-vis光谱学研究了在313-343 K的温度范围内与2b→2c转化有关的动力学。根据观察到的激活参数,提出了一种非离解异构化过程,该过程涉及一个短暂的μ2桥联膦部分。团簇2c的近紫外线照射导致CO损失和一个辅助苯基基团的邻位金属化,从而生成氢化物团簇HOs3(CO)9 [μ-PhP(C6H4)CC(PPh2)C(O)C