Iodination of <i>cyclo</i>‐E<sub>5</sub>‐Complexes (E=P, As)
Helena Brake, Eugenia V. Peresypkina, A.V. Virovets, Martin Piesch, Werner Kremer, Lisa Zimmermann, Christian Klimas, Manfred Scheer
Abstract
Abstract In a high‐yield one‐pot synthesis, the reactions of [Cp*M(η 5 ‐P 5 )] (M=Fe ( 1 ), Ru ( 2 )) with I 2 resulted in the selective formation of [Cp*MP 6 I 6 ] + salts ( 3 , 4 ). The products comprise unprecedented all‐ cis tripodal triphosphino‐cyclotriphosphine ligands. The iodination of [Cp*Fe(η 5 ‐As 5 )] ( 6 ) gave, in addition to [Fe(CH 3 CN) 6 ] 2+ salts of the rare [As 6 I 8 ] 2− (in 7 ) and [As 4 I 14 ] 2− (in 8 ) anions, the first di‐cationic Fe‐As triple decker complex [(Cp*Fe) 2 (μ,η 5:5 ‐As 5 )][As 6 I 8 ] ( 9 ). In contrast, the iodination of [Cp*Ru(η 5 ‐As 5 )] ( 10 ) did not result in the full cleavage of the M−As bonds. Instead, a number of dinuclear complexes were obtained: [(Cp*Ru) 2 (μ,η 5:5 ‐As 5 )][As 6 I 8 ] 0.5 ( 11 ) represents the first Ru‐As 5 triple decker complex, thus completing the series of monocationic complexes [(Cp R M) 2 (μ,η 5:5 ‐E 5 )] + (M=Fe, Ru; E=P, As). [(Cp*Ru) 2 As 8 I 6 ] ( 12 ) crystallizes as a racemic mixture of both enantiomers, while [(Cp*Ru) 2 As 4 I 4 ] ( 13 ) crystallizes as a symmetric and an asymmetric isomer and features a unique tetramer of {AsI} arsinidene units as a middle deck.