Synthesis, characterization, substitution, and atom-transfer reactions of ([eta][sup 2]-alkyne)(tetratolylporphyrinato)titanium(II). X-ray structure of trans-bis(4-picoline)(tetratolylporphyrinato)titanium(II)
- Iowa State Univ., Ames, IA (United States)
- Univ. of Houston, Houston, TX (United States)
A general preparative method for (tetratolylporphyrinato)titanium(II) [eta][sup 2]-acetylene complexes, (TTP)Ti([eta][sup 2]-RC[triple bond]CR[prime]), (R = R[prime] = CH[sub 3], CH[sub 2]CH[sub 3], C[sub 6]H[sub 5]; R = CH[sub 3], R[prime] = CH[sub 2]CH[sub 3]) is described. Displacement of 2-butyne from (TTP)Ti([eta][sup 2]-MeC[triple bond]CMe) with terminal acetylenes allows the preparation of (TTP)Ti([eta][sup 2]-HC[triple bond]CH) and (TTP)Ti([eta][sup 2]-PhC[triple bond]CH). The [pi] complexes undergo simple substitution reaction with pyridine (py) and 4-picoline (pic) to afford the bis(ligand) complexes trans-(TTP)Ti(py)[sub 2] and trans-(TTP)Ti(pic)[sub 2]. The structure of the bis(picoline) complex, C[sub 66]H[sub 56]N[sub 4]Ti, was determined by single-crystal X-ray diffraction (triclinic, P[bar 1]). Crystallographic symmetry requires that the Ti atom resides in the center of the 24 atom porphyrin plane. The Ti-N[sup pic] distance is 2.223(3) [angstrom], and the average Ti-N[sub pyrrole] distance is 2.047(8) [angstrom]. The two picoline ligands are coplanar, and the dihedral angle formed by the plane of the picoline rings and the Ti-N[sub 1] vector is 43[degrees]. When ([eta][sup 2]-PhC[triple bond]CPh)Ti(TTP) is treated with di-p-tolyldiazomethane, a diazo adduct (TTP)Ti=NN=C(C[sub 6]H[sub 4]CH[sub 3])[sub 2] is formed. Atom transfer occurs when ([eta][sup 2]-PhC[triple bond]CPh)Ti(TTP) is treated with X=PPh[sub 3] (X = S, Se), resulting in a two-electron oxidized product, (TTP)Ti=X, PPh[sub 3], and free PhC[triple bond]CPh. Treatment of (TTP)Ti([eta][sup 2]-PhC[triple bond]CPh) with elemental sulfur or selenium produces the perchalcogenido complexes (TTP)Ti(S[sub 2]) and (TTP)Ti(Se[sub 2]).
- OSTI ID:
- 5089134
- Journal Information:
- Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 32:20; ISSN 0020-1669; ISSN INOCAJ
- Country of Publication:
- United States
- Language:
- English
Similar Records
Synthesis and structural characterization of a Meerwein-Ponndorf-Verley/Oppenauer redox intermediate at a tantalum(V) center
Cross-coupling reactions of d sup 2 tantalum alkyne complexes: Selective 1,3-diene syntheses and their relevance to alkyne cyclization chemistry
Related Subjects
400201* -- Chemical & Physicochemical Properties
CARBOXYLIC ACIDS
CHEMICAL PREPARATION
CHEMICAL REACTIONS
COMPLEXES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
MOLECULAR STRUCTURE
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANOMETALLIC COMPOUNDS
PORPHYRINS
SYNTHESIS
TITANIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES
TRICLINIC LATTICES