Chromium cyclopentadienyl tricarbonyl

The methylation of (/(-tellurido)bis[7t5-cyclopentadienyl(tricarbonyl)]chromium by methyl trifluoromethanesulfonate in diethyl ether at 20° produced a methyltelluro-bridged complex that was isolated as the hexafluorophosphatc2. The red-brown solid forms needles that are stable in air for a short time only. 

Trichloro(tripyridine)chromium(III), synthesis 36 Tris(3-bromoacetylacetonato)chromium(III), synthesis 37 Cyclopentadienyl tricarbonyl hydrides of chromium, molybdenum, and tungsten, synthesis 38 Trichloro(tripyridine)molybdenum(III), synthesis 39 Potassium octacyanotungstate(IV) 2-hydrate, synthesis 40 Chlorine(CP )-labeled thionyl chloride, silicon tetrachloride, boron chloride, germanium (IV) chloride and phosphorus(III) chloride, synthesis 44 Unipositive halogen complexes, synthesis 46 Monopyridineiodine(I) chloride, synthesis 47 Manganese(III) acetylacetonate, synthesis 49 Triiron dodecacarbonyl, synthesis 52... 

Cyclopentadienyl tricarbonyl hydrides of chromium, molybdenum, and tungsten can be prepared by reaction of Institute for Inorganic Chemistry, The University, Munich, Germany, t Union Carbide Chemicals Company, South Charleston, W.Va. 

C2 8H2 8AS3CoCr2FeOi2 r Tricarbonyl-(dicarbonyl(tricarbonyl(cyclopenta-dienyl)chromium)cyclopentadienyl-/Li"(dimethylarsenido)chromium)-bis-M (dimethylarsenido)-(tetracarbonyliron)cobalt, 46B, 905 C28H2eCoNi04P, Di-/x"carbony1-dicarbony1(cyclohexyl(diphenyl)phosphine) (TT-methylcyclopentadienylnickelio)cobalt, 4IB, 910 C2 eH28N2S2Ti2, (2,4-Dithiopyrimidinato)bis[bis(T -methylcyclopenta-dienyl)titanium(III)], 45B, 981... 

TRICARBONYL-(ii5-CYCLOPENTADIENYL)SILYL COMPLEXES OF CHROMIUM, MOLYBDENUM, AND TUNGSTEN... 

Benzenechromium tricarbonyl (Fluorobenzene)chromium tricarbonyl Cyclopentadienyl)rhenium tricarbonyl (1,3-Cyclohexadiene)iron tricarbonyl (1,3-Cyclohexadienyl)manganese tricarbonyl (T rimethylenemethane)iron tricarbonyl (Cyclopentadienyl)manganese tricarbonyl (1,3-Butadiene)iron tricarbonyl... 

Cyclopropanation reactions of nonheteroatom-stabilized carbenes have also been developed. The most versatile are the cationic iron carbenes that cyclopropanate alkenes with high stereospecificity under very mild reaction conditions. The cyclopropanation reagents are available from a number of iron complexes, for example, (9-alkylation of cyclopentadienyl dicarbonyliron alkyl or acyl complexes using Meerwein salts affords cationic Fischer carbenes. Cationic iron carbene intermediates can also be prepared by reaction of CpFe(CO)2 with aldehydes followed by treatment with TMS-chloride. Chiral intermolecular cyclopropanation using a chiral iron carbene having a complexed chromium tricarbonyl unit is observed (Scheme 61). 

Miscellaneous Systems Other systems have been described [li,m] ferrocene/ carbon tetrachloride (a trichloromethyl radical is formed), ferrocene/carbon tetrabromide, metal carbonyl/onium salts (e.g., the [cyclopentadienyl Fe (CO)2]2/ diaryliodonium hexafluorophosphate combination where a phenyl radical is generated), benzene chromium tricarbonyl/halide derivative, and so on. 

Tricarbonyl(cyclopentadienyl)chroniium Dimer and Mercuribis[tricarbonyl(cyclopentadienyl)chromium])... 

Two methods have been reported for the preparation of cyclopentadienylchromium tricarbonyl dimer, [C5H5Cr(CO)3]2 partial oxidation of the hydride CsHsCr-(CO)sH, and the reaction of bis(cyclopentadienyl)chromium with carbon monoxide. Both of these methods suffer from the disadvantage that they require the handling of pyrophoric intermediates, and furthermore, the method involving bis (cyclopentadienyl) chromium proceeds in low yield. 

CrC5H8(CO)aH Cyclopentadienyl-chromium tricarbonyl hydride, and derivatives, 7 136, 139 sodium derivative, 7 104 [CrCsH5(CO)3l2 Cyclopenta-dienylchromium tricarbonyl, dimer, 7 104, 139 [GrC5H5(CO)3]jHg Bis(cyclo-pentadienylchromium tri-carbonyl)mercury, 7 104 [Cr(C6HsN)3Cl3 Trichloro (tri-pyridine) chromium (III),... 

Four possible general structural types are illustrated in Fig. 3. Structure types A and B are represented by the mono- and bis(tricarbonyl-chromium) complexes (ML = Cr(CO)3) and double decker and triple decker sandwich complexes (e.g. MLx = FeCp RufCgHg) CoCp ). The benzene rings of the cyclophane ligands can be replaced by cyclopentadienyl- or cyclobutadienyl-ligands. 

Beer and coworkers made several simple receptors by substituting one cyclopentadienyl ring of a ferrocene with a benzene ring, to give the amide arene CpFe 30 in Fig. 6. The same article also described the synthesis of the amide arene tricarbonyl chromium compound Downfield... 

NCrFe09P2C45H3i, Chromate(l—), hydri-dononacarbonyliron-, -nitrido-bis(triphenylphosphorus)(l +), 26 338 NCr03C7H, Chromium, dicarbonyl(r/ -cyclopentadienyl)nitro8yl-, 28 196 NCrOjCjiH, Chromium, tricarbonyl(i -NJV-dimethylbenzenamineK 28 139 NCr09C,oH9, Chromium, (tert-butyl isocyanide)pentacarbonyl-, 28 143 NCrOsCigH,3, Chromium, (benzoyl isocyanide)dicarbonyl(>t -methyl benzoate)-, 26 32... 

Tricarbonyl [ [(2,3,4,5-r/)-2,4,6-cycloheptatrien-1-yl]-trimethylgermane]iron, Ge-00173 Tricarbonyl[[(2,3,4,5- 7)-2,4,6-cycloheptatrien-l-yl]-triphenylgermane]iron, Ge-00252 Tricarbonyl-7r-cyclopentadienyl(trimethylgermyl)chromium, Ge-00138... 

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