| Summary: | 博士 === 國立臺灣大學 === 化學研究所 === 105 === A series of ruthenium acetylide complexes [Ru]−C≡C−C≡C−R ([Ru] = Cp(PPh3)2Ru) were synthesized via 1,3-butadiynes. With these long carbon chain ligands, ruthenium acetylide complex might undergo several interesting reactions. For example, treatment of the acetylide complex with an electrophilic reagent such as allyl halide, electrophilic addition on partial negative charge Cβ of the acetylide complex occurred, vinylidene complexes {[Ru]=C=C(allyl)−C≡C−R}+[PF6]- were then obtained. While treating acetylide complexes with suitable salt such as Ph3CPF6 or protic salt, pentatetraenylidene complexes {[Ru]=C=C=C=C=R}+[PF6]- were generated through the electron donation from ruthenium metal. Partial positive charge Cγ of pentatetraenylidene complexes underwent a nucleophilic addition via added alcohol or amine, ruthenium allenylidene complexes {[Ru]=C=C=C(XR′)−CH=R}+[PF6]- (X = O, N) were formed. We also observed some unexpected Cδ=Cε bond cleavage while treating ruthenium acetylide complexes [Ru]−C≡C−C(=X)−CH=R (X = O, N) with basic reagent. Proposed mechanism indicated the presence of a hydroxide ion formed from H2O attack Cε of the ruthenium complex, a ketone was then eliminated as a byproduct. Furthermore, several unsaturated bond-substituted 1,3-butadiynes were prepared. Treatment of these 1,3-butadiynes with ruthenium complex in the presence of suitable salt might cause intramolecular reactions such as cyclization.
|
|---|
