ISSN:
0009-2940
Keywords:
1,3-Diborolyl complexes, bis[η5-cyclopentadienyl)cobalt]
;
1,3-Diborolane, 4,5-diisopropylidene- and 2,4,5-triisopropylidene-
;
Benzo-1,3-diborafulvene
;
Electrochemistry
;
ESR
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
New Routes to Bis[(cyclopentadienyl)cobalt]-μ-(η5-2,3-dihydro-1,3-diborolyl) Triple-Decker Complexes by Hydrogen Shift Reactions in Derivatives of 4,5-Diisopropylidene-1,3-diborolane, 2,4,5-Triisopropylidene-1,3-diborolane, and Benzo-1,3-diborafulveneThe 31 VE dicobalt triple-decker complexes 6, 7a, 7b, c, 8a, b, and 9a, b with bridging 2,3-dihydro-1,3-diborolyl ligands are prepared. The reaction of the 1,3-diborole 1 with [(C5Me5)-Co(C2H4)2] leads to the sandwich complex 5, which is treated with [(C5H5)Co(C2H4)2] to yield unsymmetrical 6. The 4,5-diisopropylidenetrimethyl-1,3-diborolane 3 undergoes a metal-induced 1,5-hydrogen shift and reacts with [(C5H5)Co(C2H4)2] to form the triple-decker 7a. The reaction of the 2,4,5-triisopropylidene-1,3-diborolane 4 with [(C5H5)Co(C2H4)2] leads to a mixture of the triple-deckers 7b/c, formed by intermolecular hydrogen shift. The benzo-1,3-diborafulvene derivatives 2b and 2c also react with [(C5H5)Co(C2H4)2] to give the triple-decker 8b and a mixture of 9a, b. In addition, the trinuclear complex 8c is obtained in low yield. The new paramagnetic triple-decker complexes have been analyzed by NMR and ESR spectroscopic measurements as well as by electochemistry. The constitutions of 7b/c, 8b, 8c, and 9a/b have been confirmed by X-ray structure analyses. The complexes are iso-structural, the Co - Co distances range from 3.277(1) (7b/c) to 3.316(1) Å for 8c.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931261006
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