Abstract
Reactions of [RuCl(PMe3)2(Cp)] with 1-ethynylcyclohexanol or 1-ethynylcyclopentanol and NH4PF6 lead to cationic cycloalkenyl vinylidene complexes [Ru(C=CHR)(PMe3)2(Cp)][PFβ] (1, R = cyclohexenyl, and 2, R = cyclopentenyl) in ca. 80% yield. Similarly, 3-isopropyl-4-methyl-l-pentyn-3-ol (HC≡CC-(OH)(CHMe2)2) produces [Ru[C=CHC(CHMe2)(=CMe2)](PMe3)2(Cp)][PF6] (3) in 77% yield. The structure of the 1-ethynylcyclohexanol product 1 was determined by X-ray diffraction (R = 6.3%, Rw = 9.3%). The molecule contains a cyclohexenylvinylidene ligand bonded to the ruthenium atom by a short Ru-C bond (1.843 (7) Å). Complexes 1–3 are reversibly deprotonated by sodium methoxide to yield the corresponding enynyl complexes [Ru(C=CR)(PMe3)2(Cp)] (4, R = cyclohexenyl, and 5, R = cyclopentenyl) and [Ru[C≡CC(CHMe2)(=CMe2)](PMe3)2(Cp)] (6). The reaction of enynyl 4 with carbon disulfide gave a [2 + 2] cycloadduct via nucleophilic attack of the enynyl β-carbon on CS2. The reaction of 4 with methyl isocyanate gave only isocyanate polymers. Attempted reactions with other heteroallenes were not successful.
Original language | English |
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Pages (from-to) | 1972-1980 |
Number of pages | 9 |
Journal | Organometallics |
Volume | 10 |
Issue number | 6 |
DOIs | |
State | Published - Jun 1 1991 |
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry