ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Preparation and Properties of, and Reactions with, Metal-Containing heterocycles, LIX. - Synthesis and Properties of ηn2-Thiophosphinito complexes of CobaltThe η2-thiophosphinito complexes (OC)2(R2R12P)Co(η2-PR32S) (3a,b,d,e,i,j,k,m,n) are obtained by reaction of ICo(CO)2(PR3)2 (1, 2) [R = Ph (1), Cy (2)] with the secondary phosphane sulfides R32HP=S in the presence of Et(iPr)2N. The Me2PS und Et2PS compounds 3a,b,d oligomerize easily to form [(OC)2(R2R12P)Co(μ-PR32S)]n (4a,b,d) (n 〉 2). Upon exchange of PR12R2 (R1 = R2 = Ph) in 3a,d,j,m by PPh2Me, PPhMe2, and PMe3 in addition to the η2-thiophosphinito complexes 3f,g,l the dimeric species [(OC)2(R2R12P)Co(μ-PR32S)]2 (5c,f,g,h,o) are formed. The dimerization tendency depends on the steric demand of the substituents R1, R2, and R3. The substituents R1 and R2 in 5f,g are responsible for energetically preferred preferred rotamers, which are indicated in the 31P{1H}-NMR spectra. The barrier of rotation is calculated to give ΔG≠ = 42 kJ/mol. According to X-ray structural analysis (OC)2(Cy3P)Co(η2-PEt2S) (3e), [(OC)2(Me3P)Co-(μ-PMe2S)]2 (5c), and [(OC)2(Ph2MeP)Co(μ-PEt2S)]2 (5f) crystallize in the space group P21/c, P1 and P21/c with Z = 4, 2, and 2, respectively.
Notes:
Durch Umsetzung von ICo(CO)2(PR3)2 (1, 2) [R = Ph (1), Cy (2)] mit den sekundären Phosphansulfiden R23HP = S erhält man in Gegenwart von Et(iPr)2N die η2-Thiophosphinito-Komplexe (OC)2(R2R21P)Co(η2-PR23S) (3a,b,d,e,i,j,k,m,n). Die Me2PS und Et2PS-Verbindungen 3a,b,d oligomerisieren leicht unter Bildung von [(OC)2(R2R21P)Co(μ-PR23S]n (4a,b,d) (n 〉 2). Beim Austausch von PR21R2 (R1 = R2 = Ph) in 3a,d,j,m durch PPh2-Me, PPhMe2 und PMe3 entstehen neben den η2-Thiophosphinito-Komplexen 3f,g,l die dimeren Spezies [(OC)2(R21P) Co(μ-PR23S)]2 (5c,f,g,h,o). Die Dimerisierungstendenz hängt von dem sterischen Anspruch der Substituenten R1, R2 und R3 ab. Die Substituenten R1 und R2 in 5f,g sind für energetisch bevorzugte Rotamere verantwortlich, die sich in den 31P{1H}-NMR-Spektren zu erkennen geben. Die Rotationsbarriere berechnet sich zu ΔG≠ = 42 kj/mol. Nach Röntgenstrukturanalysen kristallisieren (OC)2(Cy3P)Co(η2-PEt2S) (3e), [(OC)2(Me3P)Co(μ-PMe2S)]2 (5c) und [(OC)2(Ph2MeP)Co(μ-PEt2S)]2 (5f) in der Raumgruppe P21/c, P1 bzw. P21/c mit Z = 4, 2 bzw. 2.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19881210610
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