Triosmium clusters formed by oxidative addition and decarbonylation of 2-formylpyrrole: Crystal structures of three triosmium clusters containing aromatic or nonaromatic heterocyclic ligands derived from pyrrole

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Organometallics; (USA)

DOI:https://doi.org/10.1021/om00115a002· OSTI ID:6661712

Day, M W; Hardcastle, K I ^[1]; Deeming, A J ^[2]; Arce, A J; De Sanctis, Y ^[3]

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1. California State Univ., Northridge (USA)
2. Univ. College, London (England)
3. Instituto Venezolano Investigiaciones Cientificas, Caracas (Venezuela)

The {mu}-acyl cluster (Os{sub 3}H({mu}{sub 2}-NHCH=CHCH=CCO)(CO){sub 10}) (1) is formed by oxidative addition of 2-formylpyrrole to (Os{sub 3}(CO){sub 10}(MeCN){sub 2}) in refluxing cyclohexane in the same manner as with other aldehydes. The crystals of 1 are triclinic, space group P{bar 1}, with cell dimensions a = 14.882 (2) {angstrom}, b = 15.626 (4) {angstrom}, c = 9.447 (3) {angstrom}, {alpha} = 107.39 (2){degree}, {beta} = 97.29 (2){degree}, {gamma} = 97.84 (2){degree}, and Z = 4. The structure was refined to R{sub w} = 0.034. The pyrrolylacyl ligand bridges two osmium atoms through the C and O atoms of the original formyl group. Thermal loss of two COs from 1 gives two isomers of the cluster (Os{sub 3}H{sub 2}({mu}{sub 3}-C{sub 4}H{sub 3}N)(CO){sub 9}) (2 and 3), isomer 2 converting to 3 thermally. Isomer 2, (Os{sub 3}H{sub 2}({mu}{sub 3}-NHCH=CHC=C)(CO){sub 9}), retains the NH bond and is directly related to the N-methyl analogue of 2, (Os{sub 3}H{sub 2}({mu}{sub 3}-MeNCH=CHC=C)(CO){sub 9}) (5), and closely related to the benzyne cluster (Os{sub 3}H{sub 2}(C{sub 6}H{sub 4})(CO){sub 9}), both of known X-ray structure. Cluster 2 converts to 3 by cleavage of N-H and Os-C bonds and with formation of C-H and Os-N bonds. Crystals of 3 are monoclinic, space group P2{sub 1}/c, with cell dimensions a = 11.308 (2) {angstrom}, b = 12.457 (2) {angstrom}, c = 15.384 (3) {angstrom}, {beta} = 123.59 (2){degree}, and Z = 8. The structure was refined to R{sub w} = 0.052. The structure is best defined by a model in which the {mu}{sub 3}-N=CHCH=CHC ligand is coordinated to one Os atom through a N atom and to the other two through a single C atom forming a {mu}{sub 2}-alkylidene bridge. The C{sub 4}N ring is formally nonaromatic and is oriented vertically to the metal plane.

• OSTI ID: 6661712
• Journal Information: Organometallics; (USA), Vol. 9:1; ISSN 0276-7333
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
OSMIUM COMPLEXES
CRYSTAL STRUCTURE
CLUSTER MODEL
DATA ANALYSIS
EXPERIMENTAL DATA
MEASURING INSTRUMENTS
MEASURING METHODS
ORGANOMETALLIC COMPOUNDS
PYRROLES
AZOLES
COMPLEXES
DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
MATHEMATICAL MODELS
NUCLEAR MODELS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
TRANSITION ELEMENT COMPLEXES
400200* - Inorganic
Organic
& Physical Chemistry