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[摘要]：Amphiphilic ruthenium carbenes I [R = Me(OCH2CH2)n; R1 = all-(E)-Me2C:CHCH2(CH2CMe:CHCH2)9; R2 = Me, R1; R3 = R1, Me; Cy = cyclohexyl], derived from dihydro coenzyme Q10, is prepd.; the regioisomers of I function as recyclable catalysts for the ring-closing metathesis reactions of a variety of dienes in water to give cyclic alkenes in 89-99% yields. The mixt. of I dissolves freely in water, forming nanomicelles in which ring-closing metathesis reactions on water-insol. dienes can occur in pure water at room temp.; the mixt. of I can also be recycled continuously up to nine times without reaction workup, while both the first-generation Grubbs catalyst and the Hoveyda-Grubbs catalyst can be recycled only once without substantial losses of activity. |
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