Tricarbonyl Derivatives of Manganese(I) with Diphosphinite Chelating Ligands

Reaction of MnBr(CO)₃L] L = Ph₂POCH₂CH₂OPPh₂, L¹ , {(CH₃)₂CH}₂POCH₂CH₂OP{CH(CH₃)₂}₂, L² ] with AgO₃SCF₃ and AgO₂CCF₃ in dichloromethane afforded the new complexes Mn(O₃SCF₃)(CO)₃L] and Mn(O₂CCF₃)(CO)₃L], respectively. Substitution of O₃SCF₃ resulted in the new species Mn(SCN)(CO)₃L], Mn(NCCH₃)(CO)₃L](O₃SCF₃) and, in the case of L² , Mn(CN)(CO)₃L²]. By contrast, any attempt to displace the O₂CCF₃ ligand in the same way was unsuccessful. After maintaining for some days the complex Mn(CH₃CN)(CO)₃L¹](O₃SCF₃) in dichloromethane at room temperature, the new complex MnCl(CO)₃L¹] was formed. All the new complexes were characterized by elemental analysis, mass spectrometry and IR and NMR spectroscopies. In the case of Mn(O₃SCF₃)(CO)₃L¹], Mn(O₂CCF₃) (CO)₃L¹], MnCl(CO)₃L¹], Mn(CH₃CN) (CO)₃L²] (O₃SCF₃), Mn(CN)(CO)₃L²] and Mn(O₂CCF₃)(CO)₃L²], together with the previously synthesized complex MnBr(CO)₃L²], suitable crystals for X‐ray structural analysis were isolated. In all of them the Mn atom adopts six‐coordination by bonding to the three CO ligands, the two P atoms of L and either one C atom (CN), one oxygen atom (O₂CCF₃, O₃SCF₃), one N atom (CH₃CN, SCN) or the halogen atom (Cl, Br).