Promotion of ring-opening nucleophilic addition to thietane ligands by the bridging coordination of the sulfur atom in the complexes Os{sub 3}(CO){sub 10}[{mu}-SCH{sub 2}CMe{sub 2}CH{sub 2}] and Os{sub 3}(CO){sub 10}[{mu}-trans-SC(H)MeCH{sub 2}C(H)Me]
- Univ. of South Carolina, Columbia, SC (United States)
The reaction of Os{sub 3}(CO){sub 10}[{mu}-SCH{sub 2}CMe{sub 2}CH{sub 2}] (1) with the nucleophiles F{sup -}, Cl{sup -}, Br{sup -}, I{sup -}, EtO{sup -}, Et{sub 2}NH, and (CH{sub 2}){sub 3}NH at 25 {degrees}C yielded after acidification the series of new complexes Os{sub 3}(CO){sub 10}[{mu}-SCH{sub 2}CMe{sub 2}CH{sub 2}X]({mu}-H) 9X = F, 2, 27%; X = Cl, 3, 57%; X = Br, 4, 81%; X = I, 5, 90%; X = OEt, 6, 61%; X = NEt{sub 2}, 7, 48%; X = N(CH{sub 2}){sub 3}, 8, 68%. Complex 3 was characterized crystallographically and was found to contain a bridging chloroneopentanethiolato ligand formed by the ring-opening addition of chloride to one of the methylene groups of the thietane ligand. Each of the compounds 2-8 contains similarly derived thiolato ligands. The complex Os{sub 3}(CO){sub 10}[{mu}-trans-SC(H)MeCH{sub 2}C(H)Me] (9), an equimolar mixture of the 2R, 4R and 2S, 4S enantiomers, was found to undergo a ring-opening addition of I{sup -} to yield Os{sub 3}(CO){sub 10}[{mu}-SC(H)MeCH{sub 2}C-(H)Me(I)]({mu}-H) (10), an equimolar mixture of 2R,4S and 2S,4R enantiomers formed by an inversion of stereochemistry at the iodine-substitute carbon atom. The stereochemical inversion is consistent with the conventional backside nucleophilic addition mechanism. The reaction of the complex Os{sub 3}(CO){sub 11}-[SCH{sub 2}CMe{sub 2}CH{sub 2}] (11) with chloride yielded only the known anion [Os{sub 3}(CO){sub 11}Cl]{sup -} by ligand displacement. Compounds 3 and 10 were characterized by single-crystal X-ray diffraction analyses. 19 refs., 2 figs., 7 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 539384
- Journal Information:
- Organometallics, Vol. 11, Issue 4; Other Information: PBD: Apr 1992
- Country of Publication:
- United States
- Language:
- English
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