Schwefelmonoxid als brückenligand in zwei- und dreikern-komplexen von mangan und eisen

Abstract

Summary Sulfur monoxide can be incorporated into polynuclear complexes as a bridging ligand by three different methods. The manganese complex [(C 6 H 5 ) 3 P(CO) 4 Mn] 2 SO ( 1 ) is found by nucleophilic substitution at the sulfur atom of SOCl 2 by the hydrido complex (C 6 H 5 ) 3 P(CO) 4 MnH. 1 can be oxidized to the corresponding SO 2 complex 2 , which can also be obtained from (C 6 H 5 ) 3 P(CO) 4 MnH by reaction with SO 2 Cl 2 . SO-transfer reaction occurs by fragmentation of thiirane- S -oxide, C 2 H 4 SO, in the presence of η 5 -C 5 H 5 (CO) 2 MnL (L = CO, thf) yielding the dimeric manganese compound [η 5 -C 5 H 5 (CO) 2 Mn] 2 SO ( 3 ). According to X-ray structure analysis, the SO ligand in 3 acts as a 4-electron donor oriented in a symmetrical bridge position; the four atoms of the central SOMn 2 skeleton lie exactly in a plane. 3 is also obtained by directed oxidation of the bridging sulfur of [η 5 -C 5 H 5 (CO) 2 Mn] 2 S ( 4 ) by atmospheric oxygen; reaction of η 5 -C 5 H 5 Mn(CO) 2 thf with thiirane as a novel source of sulfur yields 4 . However, only one sulfur bridge in Fe 3 (CO) 9 S 2 ( 5 ) is oxidized by m -ClPBA to give the SO cluster Fe 3 (CO) 9 S(SO) ( 6 ). The different bridge positions of the SO ligand are occupied by the various bonding systems 3c–2e (in 1 ), 3c–4e (in 3 ) and 4c–4e (in 6 ); thus the SO complexes 1, 3 and 6 are the isolobal organometallic derivatives of sulfoxides ( 1 ) sulfur trioxide ( 3 ) and sulfones ( 6 ).