Producción Científica Profesorado

Understanding and Predicting Distorted T- versus Y-Geometries for Neutral Chromous Complexes Supported by a Sterically Encumbering ?-Diketiminate Ligand



Zuno Cruz, Francisco Javier

2008

Understanding and Predicting Distorted T- versus Y-Geometries for Neutral Chromous Complexes Supported by a Sterically Encumbering ?-Diketiminate LigandHongjun Fan, Debashis Adhikari, Anas A. Saleh, Rodney L. Clark, Francisco J. Zuno-Cruz, Gloria Sanchez Cabrera, John C. Huffman, Maren Pink, Daniel J. Mindiola and Mu-Hyun BaikJ. Am. Chem. Soc. (2008), 130, 17351-17361. ISSN: 0002-7863. doi: 10.1021/ja803798b


Abstract


A series of three-coordinate Cr(II) complexes sharing the common molecular fragment (nacnac)Cr (nacnac? = [ArNC(tBu)]2CH, Ar = 2,6-iPr2C6H3) were prepared via salt metathesis with the dimer [(nacnac)Cr(?-Cl)]2. Single-crystal X-ray diffraction studies revealed that the complexes (nacnac)Cr(L) (L = CH2tBu, CH3, CH2CH3, SiH{2,4,6-Me3C6H2}2, O{2,6-iPr2C6H3}, N{CH3}2) represent a rare class of mononuclear, neutral chromium complexes with a three-coordinate high-spin chromous metal center. Depending on the nature of the third ligand, L?, these complexes can adopt either distorted T-shaped or Y-shaped coordination geometries. Density functional theory calculations and molecular orbital analyses in combination with a detailed molecular fragment energy decomposition were used to establish an intuitive concept of the key electronic structure patterns that determine the coordination geometry of preference. The frontier orbitals of the (nacnac)Cr(II) fragment direct ?-donating ligands to adopt Y-shaped geometry, whereas ligands that are primarily ?-donors prefer T-shaped coordination. The relationship between electronics at the metal center and coordination geometry was extended to include the putative neutral three-coordinate high-spin complexes of Sc(II) and Mn(II), which are predicted to both adopt Y-shaped geometry.



Producto de Investigación




Artículos relacionados

Synthesis and structural characterization of bis-chelate Pd(II) complexes derived from substituted d...

Synthesis, characterization and crystal structures of dipyridyl-N-methylimine and cloro-bis (N,N?-2,...

Versatile behavior of 2-guanidinobenzimidazole nitrogen atoms toward protonation, coordination and m...

Boron and transition metal compounds derived from 2-uroylbenzimidazole

Synthesis, characterization and crystal structures of organolead dithiolate compounds displaying tra...

Pentacoordination at Germanium by Transannular Bonding of Sulfur or Oxygen in an Eight-Membered Ring...

Determination of Glucose by Flow Injection Analysis with Amperometric Detection at Fe(III)-(tris(3,5...

Structural differences in eight- and ten-membered heterocyclic tin compounds displaying transannular...

Benzazole-N(SINGLE BOND)BH3 adducts. Reductive transposition of 2-benzimidazole, 2-benzothiazole, an...

Hexacoordinated spirocyclic germanium(IV) complex: Synthesis and structural characterization