BASISCHE METALLE. LII. SYNTHESE VON CARBENOID- UND YLIDCOBALT(III)-KOMPLEXEN AUS SUBSTITUTIONSLABILEN COBALT(I)-VORSTUFEN

Article abstract of DOI:10.1016/0022-328X(85)88035-9

The cyclopentadienylcobalt(I) compounds C5H5Co(PMe3)P(OR)3 (R=Me, Et, Prⁱ) and C5H5Co(C2H4)L (L=PMe3, P(OMe)3, CO) are prepared by ligand substitution starting from C5H5Co(PMe3)2 and C5H5Co(C2H4)2.Whereas the reaction of C5H5Co(PMe3)P(OMe)3 with CH2Br2 mainly gives Br, the dihalogenocobalt(III) complexes C5H5CoX2(PMe3) (X=Br, I) are obtained from C5H5Co(CO)PMe3 and CH2X2.Treatment of C5H5Co(CO)PMe3 or C5H5Co(C2H4)PMe3 with CH2ClI at low temperatures produces a mixture of C5H5CoCH2Cl(PMe3)I and C5H5CoCl(PMe3)I, which can be separated due to their different solubilities.The same reaction in the presence of ligand L gives the carbenoidcobalt(III) compounds PF6 in nearly quantitative yields.If NEt3 is used as the Lewis base, the ylide complexes PF6 (X=Br, I) are obtained.The PF6 salts of the dications ²⁺ (L=PMe3, P(OMe)3, CNMe) and ²⁺ are prepared either from ⁺ and L, or more directly from C5H5Co(CO)PMe3, CH2X2 and PMe3 or P(OMe)3, respectively.The synthesis of C5H5CoCH2OMe(PMe3)I is also described.