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Titolo:
Carbenerhodium(I) complexes of the half-sandwich-type: reactions with electrophiles
Autore:
Bleuel, E; Schwab, P; Laubender, M; Werner, H;
Indirizzi:
Univ Wurzburg, Inst Anorgan Chem, D-97074 Wurzburg, Germany Univ WurzburgWurzburg Germany D-97074 n Chem, D-97074 Wurzburg, Germany
Titolo Testata:
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
fascicolo: 3, , anno: 2001,
pagine: 266 - 273
SICI:
1472-7773(2001):3<266:CCOTHR>2.0.ZU;2-T
Fonte:
ISI
Lingua:
ENG
Soggetto:
TRANSITION-METAL COMPLEXES; BASIC METALS; RHODIUM COMPLEXES; BOND; C5H5RH(=C=CHR)(PPR3I); PRECURSORS; REACTIVITY; CRYSTAL; LIGAND; PROTONATION;
Keywords:
carbene complexes; cyclopentadienyl and related cycloalkenyl ligands; half sandwich complexes; organometallic; rhodium;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
32
Recensione:
Indirizzi per estratti:
Indirizzo: Werner, H Univ Wurzburg, Inst Anorgan Chem, D-97074 Wurzburg, Germany UnivWurzburg Wurzburg Germany D-97074 97074 Wurzburg, Germany
Citazione:
E. Bleuel et al., "Carbenerhodium(I) complexes of the half-sandwich-type: reactions with electrophiles", J CHEM S DA, (3), 2001, pp. 266-273

Abstract

The reaction of the carbenerhodium(I) complexes [(eta (5)-C5H5)Rh(=CR2)(L)] (R = aryl) with HX (X = Cl, CF3CO2) led, depending on the size and donor properties of the ligand L, to two different types of products. While compounds 1, 2 with R = Ph and L = CO or PMe3 react with HX to give rhodium(III)alkyls [(eta (5)-C5H5)RhX(CHPh2)(L)] 3, 4a,b, the analogues 5a and 5b withR = Ph, p-Tol and L = PPr3i afford upon treatment with HX (X = Cl, Br, I, CF3CO2) the ring-substituted products [{eta (5)-C5H4(CHR2)}RhHX(PPr3i)] 6a-e. In the presence of excess HX, the latter are converted into the dihalo or bis(trifluoroacetato) derivatives [{eta (5)-C5H4(CHR2)}RhX2(PPr3i)] 7a-e. A labelling experiment using [(eta (5)-C5D5)Rh(=CPh2)(PPr3i)] 5a-d(5) as aprecursor indicates that the migratory insertion of the carbene into a C-Hbond of the cyclopentadienyl ring probably occurs via an eta (4)-cyclopentadienerhodium(I) species as an intermediate. The triphenylphosphine complex[{eta (5)-C5H4(CHPh2)}RhCl2(PPh3)] 7f was prepared analogously from 5c andtwo equiv. of HCl. The reactions of 5a and 5d (R = Ph, L = SbPr3i) with either HBF4, [Me3O]BF4 or methyl triflate give via attack of the electrophileon the carbene carbon atom and subsequent sigma/pi rearrangement cationic eta (3)-benzylrhodium(III) complexes 9 and 10a-c in good to excellent yields. Treatment of 5a and 5d with iodine results in the cleavage of the metal-carbene bond and affords the diiodo compounds [(eta (5)-C5H5)RhI2(L)] 12a,b.

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Documento generato il 23/09/20 alle ore 13:07:13