1579977-74-4Relevant academic research and scientific papers
Base-mediated transformation of the agostic (π-allyl)-closo- rhodacarboranes into complexes with an open (1-5-η5)-pentadienyl ligand
Galkin,Dolgushin,Smol'Yakov,Sergeeva,Godovikov,Chizhevsky
, p. 5076 - 5082 (2014)
The reactions of agostic (CH3...Rh) complexes [3-{(1-3-η3)-1,1,2-trimethylallyl}-1-R-2-R′-closo-3,1, 2-RhC2B9H9] [1: R = R′ = Me; 2: R,R′ = μ-(ortho-xylylene); 3: R = Ph, R′ = Me] in a cooled (+5 °C) toluene solution with the strong non-nucleophilic base N,N,N′,N′-tetramethylnaphthalene-1,8-diamine (tmnd) formally involve a linear coupling of the π-allyl ligand of one molecule of the complex to the π-allyl ligand of the second molecule of the complex, ultimately forming the structurally novel mononuclear species [3-{(1-5-η5)-2,3- dimethyl-5-(3-methylbuten-2-yl)pentadienyl}-1-R-2-R′-closo-3,1,2-RhC 2B9H9] (4, 5) and (6a,b, a mixture of diastereomers). Complexes 5 and 6a,b were also prepared using weaker bases such as PPh3 or even EtOH instead of tmnd. All new complexes 4-6 were characterized by a combination of analytical and multinuclear NMR data, as well as by single-crystal X-ray diffraction studies of two selected species 5 and the major diastereomer of 6, which revealed an open η5-pentadienyl coordination mode of the hydrocarbon ligands in these complexes.
