ISSN:
1434-1948
Keywords:
Diene complexes
;
η3-Cyclooctatetraene metal complex
;
B(C6F5)3 addition
;
Tantalum
;
Bicyclo[5.1.0]octadienyl metal complex
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The [(η4-diene)(η5-RCp)TaCl2] complexes 6a-e (diene = butadiene, isoprene or 2,3-dimethylbutadiene; RCp = pentamethylcyclopentadienyl, methylcyclopentadienyl or cyclopentadienyl) react with cyclooctatetraene dianion (employed as [(cot)Li2]) to yield the (η4-diene)(η3-cyclooctatetraene)(η5-RCp)tantalum complexes 7. The η3-cot coordination was confirmed by an X-ray crystal structure analysis of the compound [(supine-s-cis-η4-C4H6)(η3-cot)(η5-Cp*)Ta] 7a. In solution, the cot ligand of all the complexes 7 is fluxional. Two isomers [supine and proneorientation of the (diene)CpTa subunit] were found for the (η4-butadiene)(η3-cot)CpTa system (7e/7e′ = 95:5). Complex 7e cleanly adds the organometallic Lewis acid B(C6F5)3 to yield the betaine system [(η4-C4H6){C8H8B(C6F5)3}Cp*Ta] 8, which contains a substituted bicyclo[5.1.0]octadienyl ligand.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
