Meso-rac-Ph(X)P-(CH2)4-P(X)Ph-Liganden in Komplexen des Typs (CO)4M cis(L-L), Untersuchung der Stereoisomerie durch 31 P{ 1 H}-und 13C{1 H}-NMR-Spektroskopie / Meso, rac-Ph(X)P-(CH2)4-P(X)Ph Ligands in Complexes of the Type (CO)4M cis(L-L), Investigation of Stereoisomerism by 31P{1 H} and 13 C{ 1 H} NMR Spectroscopy
1982 ◽
Vol 37
(7)
◽
pp. 841-844
◽
Abstract By reaction of M(CO)6 (M = Cr, Mo, W) with the bifunctional aminophosphane Ph(NEt2)P-(CH2)4-P(NEt2)Ph (L-L) octahedral complexes (CO)4M cis(L-L) are obtained. While it is shown by 31P{1H} NMR spectroscopy, that these complexes contain meso-and rac-(L-L) to a different extent, there is evidence from 13C{1H} NMR data obtained for the Mo complex, that the rac-ligand always prevails. As racemisation is observed when the Mo complex reacts with HBr to give (CO)4Mo-cis[Ph(Br)P-(CH2)4-P(Br)Ph] an SN1-mechanism is suggested for this reaction.