Tungsten complexes cyclopentadienyls

CYCLOPENTADIENYL)NITROSYL chromium, MOLYBDENUM, AND TUNGSTEN COMPLEXES... 

CjHjS, Thiophene, tetrahydro-gold complexes, 26 85-87 C4H,NO, 2-Propenamide, 2-methyl-nickel complex, 26 205 C4H1()02, Ethane, 1,2-dimethoxy-solvates of chromium, molybdenum, and tungsten carbonyl cyclopentadienyl complexes, 6 343 tungsten complex, 26 50 ytterbium complex, 26 22 C4H i02.NaC5H5, Ethane, 1,2-dimethoxy-compd. with cyclopentadienylsodium, 26 341... 

The anti addition of amines to the double bond of cationic (alkene)(cyclopentadienyl)di-carbonyliron complexes and to the analogous molybdenum and tungsten complexes has been reported31 33. The adducts underwent carbonyl insertion-cyclization to give chelate complexes, which were then oxidized to /8-lactams. For example, from the Fp complexes of ( )- and (Z)-2-butene the corresponding /8-lactams were obtained diastereoselectively in 10-15% yield by the direct oxidation of the benzylamine adducts with chlorine at low temperature33. The stereochemistry was determined by H-NMR spectroscopy. 

The preparations of all three (tj -CsH5)M(CO)2(NO) complexes from their corresponding [(tj -CsHs)M(CO)3] anions are similar. The experimental procedure, using the tungsten complex (dicarbonyl(i7 -cyclopentadienyl)nitrosyl-tungsten) as a typical example, is given below. 

Metal- and Cyclopentadienyl-Bound Silanol Groups in Tungsten Complexes ... 

Treatment of 7 with DMD leads to the short-lived bis-silanol A. However, this intermediate undergoes intramolecular condensation, resulting immediately in the formation of the tungsten complex 8 bearing a disiloxane unit bridging the cyclopentadienyl ligand and the metal center. 8 is... 

Half-Sandwich Tungsten Complexes with Silyl-Functionalized r -Cyclopentadienyl Ligand ... 

C4H 0., Ethane, 1,2-dimethoxy-, ytterbium complex, 26 22 solvates of chromium, molybdenum, and tungsten carbonyl cyclopentadienyl complexes, 26 343 tungsten complex, 26 50... 

PBFj02WC25H2,i, Tungsten, dicarbonyl(ti -cyclopentadienyl)[tetrafluoroborato-(1 - )](triphenylphosphine)-, 26 98 PBrFftN.,RuC 4H2i, Ruthenium(ll), tris(ace-tonitrile)bromo(ti -1,5-cyclooctadiene)-, hexafluorophosphate( I -), 26 72 PCiHv, Phosphine, trimethyl-, 26 7 tungsten complex, 27 304 C,H , Phosphine, (2,2-dimethylpropyli-dyne)-, 27 249, 251... 

Treatment of the carbyne complexes (// -cyclopentadienyl)(CO)[P(OMe)3]M = CR 1, where M = molybdenum or tungsten and R = cyclopropyl, with hydrogen chloride in diethyl ether results in a rearrangement reaction to give 7 -acyl complexes 2 in quantitative yield. 

Synthesis of heterocyclic and carbocyclic compounds via alkynyl, allyl, and propargyl organometallic cyclopentadienyl iron, molybdenium and tungsten complexes 00CRV3127. 

Dichloroiodo)benzene is commonly used as a reagent for the chlorination or oxidation of various transition metal complexes. Numerous examples of oxidative chlorination of various molybdenum and tungsten complexes with PhICl2 have been reported in the literature [67-74]. In a representative example, oxidative decarbonylation of the cyclopentadienyl complexes 83 with one equivalent of PhICh selectively yields the respective molybdenum(IV) or tungsten(IV) complexes 84 in excellent yields (Scheme 3.31) [73]. 

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