267899-07-0Relevant academic research and scientific papers
Reactivity of cyclocobaltated benzylamine derivatives toward terminal alkynes
Meneghetti, Mario Roberto,Grellier, Mary,Pfeffer, Michel,Fischer, Jean
, p. 1935 - 1939 (2000)
The cyclocobaltated complexes [(η5-C5H5)Co(4-RC6H 3CH2NMe2-C2,N)I] (1; R = H, Me, F) reacted with terminal alkynes such as R′C≡CH (2; R′ = tBu, SiMe3) to afford a mixture of the two compounds {(η5-C5H5)Co[η5-C 5H4CH=CR′(4-R-2-(CH2NMe 2)C6H3)]}+PF6- (3) and (E)-CHR′=CH(4-R-2-(CH2NMe2)C6H 3) (4) in a ca. 1:1 ratio. The reaction is rationalized by assuming that insertion of the alkyne into the Co-C bond of 1 occurred with no regio-selectivity, leading to two unstable regioisomers; a selective migration of the less hindered alkenyl-Co derivative to a Cp unit followed by migration of the monosubstituted Cp ring thus obtained to another cobalt center afforded 3, whereas compound 4 should be obtained via protiodemetalation of the other isomer formed.
