31P-NMR studies on the interaction between Rh(AA)(CO)(PPh3) complexes and free PPh3

Uncoordinated phosphine exchanges with that in Rh(AA)(CO)(PPh₃) (AA—anthranilate and phenylanthranilate ions, respectively) via an S_N2 mechanism.

---

Rh (AA) (CO) (PPh₃) (AA — ) S_N2.

     

Crystal and molecular structure of a cobalt(II) complex with bis(benzimidazol-2-ylmethyl)-methylamine (L)

The reaction product of Co(II) chloride and the title ligand L, formulated as CoLCl₂·CH₃OH, was prepared and characterized by means of structural and spectroscopic measurements. The violet crystals are orthorhombic, (space groupP2₁2₁2₁) witha=8.093(2),b=14.883(3),c=16.831(3) Å, andZ=4. The structure consists of discrete molecules with pseudo-, noncrystallographic twofold symmetry in which the Co atom is coordinated in trigonal bipyramidal geometry by three nitrogen and two chlorine atoms. The ligand L is coordinated to the Co atom in afac mode and two chlorine atoms are incis-positions. The structure was confirmed by IR-spectra.     

Synthesis and reactivity of rhodium(I) complexes of the type Rh(L-L)(CO)[P(OPh)3] and Rh(L-L)[P(OPh)3]2

Summary The carbonyl ligands in the Rh¹ complexes Rh(L-L)(CO)₂ [L-L=anthranilate (AA) orN-phenylanthranilate(FA) ions] are replaced by P(OPh)₃ to form the mono-or disubstituted products, Rh(L-L)(CO)[P(OPh)₃] and Rh(L-L)[P(OPh)₃]₂ respectively depending on the [P(OPh)₃]/[Rh] molar ratio, at room temperature and in air. Under argon at [P(OPh)₃]/[Rh]4 theortho-metallated Rh¹ complex Rh[P(OPh)₃]₃[P(OC₆H₄)-OPh)₂] is formed. The new route forortho-metallated Rh¹ complex synthesis is described.The Rh(AA)(CO)₂ complex was used as a catalyst precursor in hydroformylation of olefins.     

Synthesis,crystal and molecular structure of the novel complex [dinitrato{N,N-bis(1–methylbenzimidazol-2–ylmethyl)methylamine}]cobalt(II)

Co(NO3)2·6H2O reacts with N,N-bis(1–methylbenzimidazol-2–ylmethyl)methylamine (Me2L) in MeOH/ Et2O solution at ca. 5°C, yielding a novel, penta-coordinate complex, formulated as [Co(NO3)2(Me2L)], which was characterized by means of structural, spectroscopic and magnetic measurements. The Co atom is coordinated in distorted trigonal bipyramidal geometry by three N and two O atoms. The ligand Me2L is coordinated in a facial mode and two coordinated O atoms from the nitrato ligands are in cis-positions.