164072-10-0Relevant articles and documents
Carbamoyl (Carboxamido) Complexes as Precursors for Metallaoxetene, Isonitrile, and Aminomethylidyne Complexes of Iron
Anderson, Stephen,Hill, Anthony F.,Ng, Ying Thong
, p. 15 - 21 (2000)
The reaction of [Fe{C(=O)NiPr2}(CO)4]Li with (CF3CO)2O in diethyl ether followed by triphenylphosphine provides carbamoyl complexes [Fe{η2-OCNiPr2}(CF3)(CO) 2(PPh3)] (1) or [Fe(η2-OCNiPr2)(CO)2(PPh 3)2](O2CCF3) (2a·O2CCF3) depending on the reaction conditions. The same procedure performed in dichloromethane provides the aminomethylidyne complex [Fe(≡CNiPr2)(CO)3(PPh 3)](O2CCF3) (5·O2CCF3) as well as traces of [Fe(η2-OCNiPr2)(CO)2-(PPh 3)2](O2CCF3) (2a·O2CCF3). The reactions of 1 with moist AgBF4 or HBF4 provide [Fe-{η2-OCNiPr2}(CO)3(PPh 3)]BF4 (2b·BF4), via a putative difluorocarbene intermediate, [Fe{η2-OCNiPr2}(=CF2)(CO) 2(PPh3)]BF4. In a similar manner, [Fe(η2-OCNiPr2)(CF3)(CO)(dPPe)] (3) (obtained from 1 and dppe) reacts with HBF4(aq) to provide [Fe{η2-OCNiPr2}(CO) 2(dppe)]-BF4 (4·BF4). A difluorocarbene complex is also implicated in the formation of the ferraoxetene [Fe{κ2-C(NiPr2)OCF 2}(CO){HB(pz)3}] (6) (pz = pyrazol-1-yl), which results from treatment of 1 with K[HB(pz)3] under high dilution. Under more concentrated conditions [Fe{HB(pz)3}2] is obtained. The ferraoxetene undergoes an unusual acid hydrolysis with HBF4(aq)/CO to provide the isonitrile salt [Fe(CNiPr)(CO)2{HB(pz)3}]PF6 (7·PF6). The salt [Fe(≡CNiPr2)-(CO)3(PPh3)]I (5·I) is the product of the reaction of 1 with iodine, via an as yet obscure mechanism, which may however also involve ferraoxetene intermediates.
Dihapto carbamoyl (carboxamide) complexes of iron(II)
Anderson, Stephen,Berridge, Timothy E.,Hill, Anthony F.,Ng, Ying Thong,White, Andrew J.P.,Williams, David J.
, p. 2686 - 2693 (2008/10/09)
The carbamoyl ferrate Li[Fe{C(=O)NiPr2}(CO) 4] reacts in diethyl ether with Br2PPh3, I 2PPh3, or I2 followed by triphenylphosphine to provide the complexes [Fe(η2-OCNiPr 2)X-(CO)2(PPh3)] [X = I trans to PPh 3 (1a); Br (1b) two isomers], each of which feature dihaptoC,O carbamoyl coordination. The reactions of 1a or 1b with AgBF4 in the presence of CO provide [Fe(η2-OCNiPr 2)(CO)3(PPh3)]BF4 (2a·BF 4), one carbonyl ligand of which is labile and readily replaced by I-, Br-, or PPh3 to provide 1a, 1b, or [Fe-{η2-OCNiPr2}(CO)2(PPh 3)2]BF4(2b·BF4). The reaction of 1a with dppe leads to a separable mixture of the salt [Fe{η2- OCNiPr2}(CO)2(dppe)]I (3·I) and [Fe{η2-OCNiPr2}I(CO)(dppe)] (4). Successive treatment of Li[Fe{C(=O)NiPr2}(CO)4] with ClSnPh3 and PPh3 provides the stannyl complex [Fe(η2-OCNiPr2)(SnPh3)(CO) 2(PPh3)] (1d). Treating Id with iodine leads to Sn-Fe rather than Sn-C cleavage and formation of 1a. In all the above transformations the integrity of the dihapto carbamoyl coordination is ultimately retained. The crystal structures of 1d and 2b·PF6 are reported.
Two counterintuitive routes to an iron alkylidyne complex
Anderson, Stephen,Hill, Anthony F.
, p. 1562 - 1564 (2008/10/09)
The cationic aminomethylidyne complex [Fe-(≡CNiPr2)(CO)3(PPh3) + has been prepared by two unexpected routes: (i) Iodination of the carbamoyl complex [Fe(η2-OCNiPr2)(CF3)(CO) 2(PPh3)] and (ii) O-trifluoro-acetylation of the carbamoylate [Fe{C(=O)NiPr2}(CO)4]-Li, a reaction which shows an unusual solvent dependence.
