Absolute configurations of organometallic compounds. III. Structure and absolute configuration of the square-pyramidal complex ((+)/sub 579/-(C/sub 5/H/sub 5/)Mo(CO)/sub 2/(NN*))PF/sub 6/(NN* = Schiff base derived from pyridine-2-carbaldehyde and (S)-(-)-. cap alpha. -phenylethylamine)

Journal Article · Wed Feb 01 00:00:00 EST 1978 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic50180a041· OSTI ID:5149198

Bernal, I; LaPlaca, S J; Korp, J; Brunner, H; Herrmann, W A

The structure of (+)/sub 579/-(eta/sup 5/-C/sub 5/H/sub 5/Mo(CO)/sub 2/(NN*))PF/sub 6/ with NN* = the Schiff base derived from pyridine-2-carbaldehyde and (S)-(--)-..cap alpha..-phenylethylamine was determined using standard single-crystal x-ray diffraction methods. The absolute configuration was determined by refinement of the data using the anomalous scattering contributions of Mo and P to a final R(F) = 0.056 for 2634 independent reflections having I greater than 3 sigma (I). The substance crystallizes in the space group P2/sub 1/2/sub 1/2/sub 1/ with unit cell dimensions of a = 12.249 (4), b = 9.236 (3), and c = 20.692 (9) A and Z = 4 molecules/unit cell. The square-pyramidal coordination of the Mo atom is defined by two carbonyl carbons and two Schiff base nitrogens occupying the four basal plane sites and the five carbons of the eta/sup 5/-C/sub 5/H/sub 5/ ligand in the axial position. The Mo--ligand distances and the bond lengths and angles within the ligands are normal and compare closely with those of recent structure determinations of comparable precision. The Mo atom is 0.95 A above the plane formed by the four basal plane ligands. The conformation of the (S)-..cap alpha..-phenylethyl group with respect to the ligand plane, defined by the pyridine ring, the imine system, and the Mo atom, is discussed. The configuration at the metal atom in the (+)/sub 579/ isomer is specified as (S). The PF/sub 6//sup -/ anion executes large amplitude torsional motion in the lattice, as is commonly the case for this anion when not hydrogen bonded.

• Research Organization: Brookhaven National Lab., Upton, NY
• OSTI ID: 5149198
• Journal Information: Inorg. Chem.; (United States), Vol. 17:2
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
FLUORINE COMPOUNDS
CRYSTAL STRUCTURE
MOLYBDENUM COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANOMETALLIC COMPOUNDS
X-RAY DIFFRACTION
COHERENT SCATTERING
DIFFRACTION
HALOGEN COMPOUNDS
ORGANIC COMPOUNDS
SCATTERING
TRANSITION ELEMENT COMPOUNDS
400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)