ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Basic Metals, XXX. Reactivity and Dynamics of the Complexes C5H5Co(PR3)2 (R = Me, Et), (C5H4R)Co(PMe3)2, and C5H3RR)Co(PMe3)2: Influence of Steric Effects on the Lewis Basicity of Electron-rich MetalsThe complex C5H5Co(PMe3)2 (1) reacts with secondary and tertiary alkyl halides RX (R = CHMe2, CMe3. CMe2Et) to give the cations [(C5H4R)CoH(PMe3)2]+ which after reduction with NaH form the neutral compounds (C5H4R)Co(PMe3)2) (5-7). These are used as starting materials for the preparation of the disubstituted complexes [C5H3RR)CoH(PMe3)2]PF6 (15-17), (C5H3RR)Co(PMe3)2) (18-20) und [(C5H3RR)CoCH3(PMe3)2] 1 (21-23) (R = CHMe2, CMe3). In the compounds with R = R= CMe3 rotation about that metal-ring bond is so hindered the rigid conformers are present at 25-100°C. Similarly, a frozen conformation of the complex [C5H3(CHMe2)CMe3]Co(PMe3)2 (19) is evident below -10°C. The preparation of the complexes [C5H3RR)CoH(PMe3)2]PF6 (26-28), [C5H3(SiMe3)R]Co(PMe3)2 (27-29) (R = H, CHMe2) and C5H5Co(PEt3)2 (10) is also described and their dynamics as well as their reactivity are investigated.
Notes:
Der Komplex C5H5Co(PMe3)2 (1) reagiert mit sekundären und tertiären Alkylhalogeniden RX (R = CHMe2, CHe3, CMe2Et) zu den Kationen [(C5H4R) CoH(PMe3)2]+, die nach Reduktion mit NaH die Neutralverbindungen (C5H4Co(PMe3)2) (5-7) ergeben. Aus diesen werden die zweifach ringsubstituierten Komplexe [C5H3RR′)CoH(PMe3)2]PF6 (15-17), (C5H3RR′)Co(PMe3)2) (18-20) und [(C5H3RR′)CoCH3(PMe3)2] 1 (21-23) (R′ = CHMe2, CMe3) Synthetisiert. In den Verbindungen mit R = R′ =CMe3 ist die Rotation um die Metall-Ring-Bindung so stark behindert, daß bei 25-100°C starre Konformere vorliegen. Für [C5H3(CHMe2CMe3]Co(PMe3)2 (19) ist unterhalb -10°C ebenfalls eine eingefrorene Konformation nachweisbar. Die Komplexe [C5H3(SiMe3)R)CoH(PMe3)2]PF6 (26-28), [C5H3(SiMe3)R)]CoH(PMe3)2 (27-29) (R = H, CHMe2) und C5H5Co(PEt3)2 (10) werden ebenfalls dargestellt und ihr dynamisches Verhalten sowie ihre Reaktivität untersucht.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19811140803
