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Z-Selective olefin metathesis reactions promoted by tungsten oxo alkylidene complexes.

ABSTRACT: Addition of LiOHMT (OHMT = O-2,6-dimesitylphenoxide) to W(O)(CH-t-Bu)(PMe(2)Ph)(2)Cl(2) led to WO(CH-t-Bu)Cl(OHMT)(PMe(2)Ph) (4). Subsequent addition of Li(2,5-Me(2)C(4)H(2)N) to 4 yielded yellow W(O)(CH-t-Bu)(OHMT)(Me(2)Pyr)(PMe(2)Ph) (5). Compound 5 is a highly effective catalyst for the Z-selective coupling of selected terminal olefins (at 0.2% loading) to give product in >75% yield with >99% Z configuration. Addition of 2 equiv of B(C(6)F(5))(3) to 5 afforded a catalyst activated at the oxo ligand by B(C(6)F(5))(3). 5·B(C(6)F(5))(3) is a highly active catalyst that produces thermodynamic products (~20% Z).

SUBMITTER: Peryshkov DV

PROVIDER: S-EPMC3244563 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Z-Selective olefin metathesis reactions promoted by tungsten oxo alkylidene complexes.

Peryshkov Dmitry V DV Schrock Richard R RR Takase Michael K MK Müller Peter P Hoveyda Amir H AH

Journal of the American Chemical Society 20111130 51

Addition of LiOHMT (OHMT = O-2,6-dimesitylphenoxide) to W(O)(CH-t-Bu)(PMe(2)Ph)(2)Cl(2) led to WO(CH-t-Bu)Cl(OHMT)(PMe(2)Ph) (4). Subsequent addition of Li(2,5-Me(2)C(4)H(2)N) to 4 yielded yellow W(O)(CH-t-Bu)(OHMT)(Me(2)Pyr)(PMe(2)Ph) (5). Compound 5 is a highly effective catalyst for the Z-selective coupling of selected terminal olefins (at 0.2% loading) to give product in >75% yield with >99% Z configuration. Addition of 2 equiv of B(C(6)F(5))(3) to 5 afforded a catalyst activated at the oxo ...[more]

PMID: 22107254

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