om801191f_si_002.pdf (49.91 kB)

Synthesis and Characterization of Conjugated Diallenes and Their Binuclear Ruthenium η3-Allyl Complexes

Download (49.91 kB)
journal contribution
posted on 11.05.2009, 00:00 by Jian-Long Xia, Xianghua Wu, Yinghui Lu, Gang Chen, Shan Jin, Guang-ao Yu, Sheng Hua Liu
A series of conjugated diallenes (CH2CCHRCHCCH2; R = 1,4-C6H4, 4,4′-C6H4-C6H4, 4,4′-C6H4CHCHC6H4, 4,4′-C6H4NNC6H4, 4,4′-C6H4CCC6H4) have been prepared by copper-catalyzed reactions of the corresponding diacetylenes with paraformaldehyde and diisopropylamine. Treatment of these conjugated diallenes with [RuHCl(CO)(PPh3)3] produced the binuclear ruthenium η3-allyl complexes [(PPh3)2(CO)ClRu]2[(η3-CH2CHCH)2R], all of which have been characterized by elemental analysis, ES-MS, 1H and 31P{1H} NMR spectrometry, IR spectroscopy, and UV/vis spectrophotometry, as well as by cyclic and square-wave voltammetry. These bimetallic complexes showed a remarkable absorption in the visible region (λmax: 380−451 nm), and the complex [(PPh3)2(CO)ClRu]2[(η3-CH2CHCH)2(C6H4NNC6H4)] (9) was found to undergo trans-to-cis isomerization under irradiation with UV light. Electrochemical study has shown that the two metal centers in complex [(PPh3)2(CO)ClRu]2[(η3-CH2CHCH)2C6H4] (6) interact with each other.