ISSN:
1572-901X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary Diazadienes (DAD) (RN=CR′CR′=NR with R′=H or Me and R=n-,i- ort-alkyl, aryl oro,o′-substituted aryl) easily form the thermally inert title compounds [(DAD)-Ru(CO)2I2] (2). Their stereochemistry is unambiguously derived from1H-n.m.r. and i.r. data. One of the complexes (2h) cocrystallizes with the free diazadiene (1h) in a 1∶1 molar ratio. An x-ray diffraction study, which allows a comparison of the free and bound diazadiene. was performed with the monoclinic crystal and gave the following cell parameters: space group C 2/c, a=2237.0(5), b=1017.4(3) and c=1824.9(4) pm, β=105.13(2)°, Z=4. From 2781 observed reflections 293 parameters were refined, leading to a final R-value of 0.0346 (Rw=0.0340). The tilting of thep-tolyl group is a consequence of an intra-ligand repulsion R/R′, the R-conformation being almost equal in the (E,E,E)-shaped molecule (1h) (68°) and the (E,Z,E)-chelate in (2h) (72°). Complexes (2) are photolabile (with loss of CO), and on reduction they lose iodide, thus offering selective ways for the exchange of π-acceptor or σ-donor ligands for precatalyst formation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01225982
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