Chromium dicarbonyl nitrosyl

As mentioned above, ICR spectrometers have been used as research tools for the investigation of gas phase ion-molecule reactions. An example of the sort of ion-molecule study which can be carried out by FT-ICR techniques but which would be beyond the capability of any other technique is the study of the ion-molecule condensation chemistry of the three organometallic compounds, ijS.cydopentadienyl manganesetricarbonyl (CpMn(C0)3), j, 176-cyclopentadienyl chromium-dicarbonyl nitrosyl (CpCr(C0)2N0), 2, and- j5 cyclopentadienyl chromiumdicarbonylthionitrosyl (Cprr(C0)2NS),. Compounds and form an isoelectronic pair 2 and 3 are a congener pair. 

Structural studies of large molecules may be illustrated by cyclopentadienyl chromium dicarbonyl nitrosyl ( ) —C5 H5)Cr(CO)2NO, a simple piano-stool-type configuration. Interest in these metal-nitrosyl compounds arises since NO is a neurotransmitter. A study of various iso-tomers gives the overall molecular configuration and structure of Fig. 15. 

NCrFeO,P2C45H3, Chromate(l-), hydrido-nonacarbonyliron-, j-nitrido-bis(tri-phenylphosphorus)(l+), 26 338 NCr03C,Hj, Chromium, dicarbonyl(T] -cyclopentadienyl)nitrosyl-, 28 196 NCr03C H, Chromium, tricarbonylit] -lV, -dimethylbenzenamine)-,... 

Dicarbonyl Nitrosyl Complexes Chromium, Molybdenum, and Tungsten 197... 

NCrFe09P2C49H3, Chromate(l—X hydri-dononacarbonyliron-, p-nitrido-bis(triphenylphosphorus)(l +), 26 338 NCr03C7H], Chromium, dicarbonyl(> -cyclopentadienyl)nitrosyl-, 28 196 NCr03CiiH,i, Chromium, tricarbonyl(q -N,AI-dimethylbenzenamine)-, 28 139 NCrOgCioHj, Chromium, (tert-butyl isocyanide)pentacaibonyl-, 28 143 NCrOgCiiHig, Chromium, (benzoyl isocyamde)dicarbonyl(i -methyl benzoatcK 26 32... 

The chemistry of the dicarbonyl(7 -cyclopentadienyl)nitrosyl and the chloro-(i7 -cyclopentadienyl)dinitrosyl complexes of chromium, molybdenum, and tungsten [i.e., fT -CsHs)M(CO)j(NO)] and [(i7 -CsHs)M(NO)2Cl] has not been studied extensively, partly because of the various difficulties associated with their preparation. The procedures described below are of general applicability to all three metals and lead to the desired compounds in high yields. The carbonyl nitrosyl complexes are the synthetic precursors of the chloro nitrosyl complexes and so their preparation is described first. 

A. DICARBONYL(t -CYCLOPENTADIENYL)NITROSYL complexes of CHROMIUM, MOLYBDENUM, AND TUNGSTEN... 

Steric interactions also influence the ground-state stability and barrier heights of the (R,R)-(S,S) and (R,S)-(S,R) diastereomers found in (rf-C5H5)Fe(CO)[Sn(CH3)3](CH3CH==CH2) (56). The olefin in one pair of diastereomers is significantly more labile. Diastereomers can also be detected by both IR and NMR in (Tj -CsHsIMfCOKNOKolefin) where M = Cr, Mo, and W (57, 60, 66). Approximately equal amounts of the diastereomers of the chromium complexes may be prepared readily by irradiation of the nitrosyl dicarbonyl complex in the presence of an olefin, such as propene or styrene (66). 

O3NSC7HS, l,2-Benzisothiazol-3(2//)-one, 1,1-dioxide, chromium and vanadium complex, 27 307, 309 O3NWC7H5, Tungsten, dicarbonyl(i -cyclopentadienyl)nitrosyl-, 28 196 03N3MoC,2H, Molybdenum,... 

C2 8H2 6CrIN03P2, tranS Dicarbonyl trans-bis(methyldiphenylphosphine)-iodo(nitrosyl)chromium, 42B, 973... 

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