300575-00-2Relevant academic research and scientific papers
Reactions of cationic bridging carbyne complexes of bis(η-cyclopentadienyl)diiron tricarbonyl with nucleophiles. A route to diiron bridging carbene complexes
Liu, Yajun,Wang, Ruitao,Sun, Jie,Chen, Jiabi
, p. 3498 - 3506 (2008/10/08)
The reactions of the cationic carbyne complex of diiron, [Fe2(μ-CO)(μ-CPh)(CO)2(η-C5H5) 2]- BBr4 (3), with NaSMe, NaSEt, NaSPh, NaSC6H4Me-p, and NaSC6H4NO2-p in THF at low temperature afforded diiron bridging thiocarbene complexes [Fe2(μ-CO){μ-C(SR) Ph}(CO)2-(η-C5H5)2] (5, R = Me; 6, R = Et; 7, R = Ph; 8, R = p-MeC6H4; 9, R = p-NO2C6H4). Complex [Fe2(μ-CO)(μ-CC6 H4Me-p)(CO)2(η-C5H5)2]BBr4 (4) reacted similarly with NaSPh and NaSC6H4-Me-p to give corresponding bridging carbene complexes [Fe2(μ-CO){μ-C(SR)C6 H4Me-p}(CO)2-(η-C5H5)2] (10, R = Ph; 11, R = p-MeC6H4). Complex 3 also reacted with NaOPh and NaN(SiMe3)2 to yield bridging carbene complexes [Fe2(μ-CO){μ-C(OPh)Ph}(CO)2(η- C5 H5)2] (12) and [Fe2(μ-CO){μ- C(N(SiMe3)2)Ph}(CO)2(η-C5H5) 2] (13), respectively. Complexes 3 and 4 reacted with reactive salt [Et3NH][Fe2(μ-CO)(μ-SBun)(CO)6 ] to yield the bridging mercaptocarbene complex [Fe2(μ-CO) {μ-C(SH)Ph}(CO)2(η-C5H5)2] (14) and the bridging butylthiocarbene complex [Fe2(μ-CO){μ-C(SBun)C6H4 Me-p}(CO)2(η-C5H5)2] (15), respectively. The analogous reactions of [Et3NH][Fe2(μ-CO) (μ-SPh)(CO)6] with 3 and 4 afforded the thiolato-bridge iron carbonyl compound [Fe2(μ-SPh)2(CO)6] (16) and the bridging arylcarbene complexes [Fe2(μ-CO){μ-C(H)Ar}(CO)2(η-C$ -5$/ H5)2] (17, Ar = Ph; 18, Ar = p-MeC6H4), while [Et3NH][Fe2(μ-CO)(μ-SC6H4Me-p) (CO)6] reacted with 3 to yield 17 and [Fe2(μ-SC6H4Me-p)2-(CO)6] (19). The reaction of metal carbonyl anion compounds Na2W(CO)5 and Na2Fe(CO)4 with 3 gave the same product, 17. The structures of 6, 7, 15, and 17 have been established by X-ray diffraction studies.
Selective formation of one or two C-C bonds promoted by carbanion addition to [Fe2(cp)2(CO)2(μ-CO)(μ-CSMe)]+
Bordoni, Silvia,Busetto, Luigi,Camiletti, Chiara,Zanotti, Valerio,Albano, Vincenzo G.,Monari, Magda,Prestopino, Fabio
, p. 1224 - 1232 (2008/10/08)
The reactions of [Fe2(cp)2(CO)2(μ-CO)(μ-CSMe)]CF 3SO3 (1; cp = η-C5H5) with a variety of carbon nucleophiles result in C-C bond formation at different sites of the molecule, (allyl)-MgCl (allyl = C3H5) undergoes cp addition to form [Fe2(cp)(η4-C5H5-allyl)(CO) 2(μ-CO)(μ-CSMe)] (2) and the alkylidene complex [Fe2(cp)(η-C5H4-allyl) (CO)2(μ-CO){μ-C(SMe)H}] (3), derived from cp to μ-C hydrogen migration. Li2Cu(CN)R2 adds at the μ-C atom to yield [Fe2(cp)2(CO)2(μ-CO){μ-C(SMe)R}] (R = Ph, 4; R = Me, 8), [FeFe(cp)2(CO)(μ-CO){μ-C(SMe)R}] (R = Ph, 5; R = Me, 9), and [Fe2(cp)2(CO)(μ-CO){μ-C(ηl2-Ph)Ph}] (6) or the vinylidene derivative [Fe2(cp)2(CO)(μ-CO)(μ-C=CH2)] (10) in the case of phenyl or methyl organocuprate reagents, respectively. The latter complexes are the result of C-SMe bond breaking occurring, through different reaction paths, in 4 and 8. Likewise, the formation of [Fe2-(cp)2(CO)(μ-CO){μ-C=C(CN)2}] (11) from 1 and NaCH(CN)2 occurs via a direct addition at the μ-C carbon followed by HSMe elimination. The nucleophilic attack at the terminal CO in 1 is achieved with LiC≡CPh, which forms two new C-C bonds in the alkylidene complex [FeFe(cp)2(CO)(μ-CO){μ-C(SMe)C(O)CCPh}] (12) after C(O)CCPh migration from Fe to the bridging carbene carbon. The analogous [FeFe(cp)2(CO)(μ-CO)(μ-C(SMe)C(O)(2-th)}] (13; 2-th = 2-C4H3S) and [Fe2(cp)(η4-C5H5-(2-th)(CO) 2(μ-CO)(μ-CSMe)] (14) are obtained from 1 and Lith via addition at the CO and cp groups, respectively. The relevance of these reactions is discussed in terms of selective C-C bond formation that, if it occurs at the cp or CO terminal ligands, favors the hydrogen migration (e.g. formation of 3) or the carbyne-carbonyl migratory coupling (e.g. formation of 12 and 13), respectively. The X-ray structures of [Fe2-(cp)2(CO)(μ-CO){μ-C(η2-Ph)Ph}] (6) and [FeFe(cp)2(CO)(μ-CO){μ-C(SMe)C(O)(2-th)}] (13) have revealed the peculiarity of the Ph and SMe group coordination to the iron. Their structural features are discussed in comparison with those of analogous complexes.
