Reaction of [{WBr2(CO)4}2] with CF3C≡CCF3 in pentane affords the bis(alkyne) complex [WBr2(CO)(CF3C≡CCF3)2] (I) in which the carbonyl ligand appears to function as a σ-donor ligand only, according to IR data. I reacts with P(OMe)3 and P(OEt)3 to give dimeric complexes II (R = Me, Et) contg. a novel vinylphosphonate ligand resulting from a Michaelis-Arbuzov type elimination of alkyl bromide. The structure of the complex with R = Et has been detd. by x-ray anal. The tungsten coordination is octahedral with mutually cis carbonyl and σ-alkenyl carbon atoms both trans to μ-Br groups, and with phosphate O trans to a four-electron donor η2-CF3C≡CCF3. The bonding in the novel vinyl phosphonate W[C(CF3):C(CF3)P(OEt)2O] chelate ring is discussed.
Synthesis and reactions of the coordinatively unsaturated hexafluorobut-2-yne complex [WBr2(CO)(CF3C≡CCF3)2]. The crystal and molecular structure of di-μ-bromobis{carbonyl[3-(diethoxyphosphoryl)hexafluorobut-2-en-2-yl](η-hexafluorobut-2-yne)tungsten}
VASAPOLLO, Giuseppe;
1987-01-01
Abstract
Reaction of [{WBr2(CO)4}2] with CF3C≡CCF3 in pentane affords the bis(alkyne) complex [WBr2(CO)(CF3C≡CCF3)2] (I) in which the carbonyl ligand appears to function as a σ-donor ligand only, according to IR data. I reacts with P(OMe)3 and P(OEt)3 to give dimeric complexes II (R = Me, Et) contg. a novel vinylphosphonate ligand resulting from a Michaelis-Arbuzov type elimination of alkyl bromide. The structure of the complex with R = Et has been detd. by x-ray anal. The tungsten coordination is octahedral with mutually cis carbonyl and σ-alkenyl carbon atoms both trans to μ-Br groups, and with phosphate O trans to a four-electron donor η2-CF3C≡CCF3. The bonding in the novel vinyl phosphonate W[C(CF3):C(CF3)P(OEt)2O] chelate ring is discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
