Synthesis and Multiple Subsequent Reactivity of Anionic <i>cyclo</i>‐E<sub>3</sub> Ligand Complexes (E=P, As)
Martin Piesch, Stephan Reichl, Michael Seidl, Gábor Balázs, Manfred Scheer
Abstract
Abstract A synthetic pathway for the synthesis of novel anionic sandwich complexes with a cyclo‐E 3 (E=P, As) ligand as an end deck was developed giving [Cp′′′Co(η 3 ‐E 3 )] − (Cp′′′=1,2,4‐tri‐tert‐butylcyclopentadienyl, E=P ([ 5 ]), As ([ 6 ])) in good yields suitable for further reactivity studies. In the reaction with the chlorophosphanes R 2 PCl (R=Ph, Cy, t Bu), neutral complexes with a disubstituted cyclo‐E 3 P (E=P, As) ligand in [Cp′′′Co(η 3 ‐E 3 PR 2 )] (E=P ( 7 a – c ), As ( 9 a – c )) were obtained. These compounds can be partially or completely converted into complexes with a cyclo‐E 3 (E=P, As) ligand with an exocyclic {PR 2 } unit in [Cp′′′Co(η 2 :η 1 ‐E 3 PR 2 )] (E=P ( 8 a – c ), As ( 10 a – c )). Additionally, the insertion of the chlorosilylene [LSiCl] (L=( t BuN) 2 CPh) into the cyclo‐E 3 ligand of [ 5 ] and [ 6 ] was achieved and the novel heteroatomic complexes [Cp′′′Co(η 3 ‐E 3 SiL)] (E=P ( 11 ), As ( 12 )) could be isolated. The reaction pathway was elucidated by DFT calculations.