Yttrium(III) chloride complexes [YCl2(NNOH)] (1H) and [YCl2(NNOMe)] (1Me) {NNOH = 2-tert-butyl-6-(quinolin-8-yliminomethyl) phenoxide; NNOMe = 2-tert-butyl-6-[(2-methylquinolin- 8-ylimino)methyl]phenoxide} were synthesized by treating a thf solution of YCl3 at room temperature with the NNOH-H and NNOMe-H ligands {NNOH-H = 2-tert-butyl-6- (quinolin-8-yliminomethyl)phenol; NNOMe-H = 2-tert-butyl- 6-[(2-methylquinolin-8-ylimino)methyl]phenol}, which were previously deprotonated with potassium tert-butoxide or thallium ethoxide. Surprisingly, reaction of 1H with the Grignard reagent MeMgBr to prepare the corresponding dialkyl derivative led to the formation of the tetranuclear magnesium dimer [Mg2BrCl{NN(Me)OH}(thf)]2 {NN(Me)OH = 2-tert-butyl-6-[1-(quinolin-8-ylamido)ethyl]phenoxide} (2), whose structure was determined by single-crystal X-ray diffraction. By reacting the neutral ligand NNOH-H with Y(CH2SiMe3)3·2thf in toluene at low temperature the alkyl complex [Y(CH2SiMe3){NN(CH2SiMe3)O}(thf)] {NN(CH2Si- Me3)O = 2-tert-butyl-6-[1-(quinolin-8-ylamido)-2-trimethylsilanylethyl] phenoxide} (3) was isolated. The supposed reaction mechanism leading to the formation of 3 was simulated by using the PM6 Hamiltonian.
Reactivity of Yttrium Quinoline–Imine–Phenoxide Complexes Towards Inter and Intramolecular Alkyl Nucleophilic Attack
BERTOLASI, Valerio
2008
Abstract
Yttrium(III) chloride complexes [YCl2(NNOH)] (1H) and [YCl2(NNOMe)] (1Me) {NNOH = 2-tert-butyl-6-(quinolin-8-yliminomethyl) phenoxide; NNOMe = 2-tert-butyl-6-[(2-methylquinolin- 8-ylimino)methyl]phenoxide} were synthesized by treating a thf solution of YCl3 at room temperature with the NNOH-H and NNOMe-H ligands {NNOH-H = 2-tert-butyl-6- (quinolin-8-yliminomethyl)phenol; NNOMe-H = 2-tert-butyl- 6-[(2-methylquinolin-8-ylimino)methyl]phenol}, which were previously deprotonated with potassium tert-butoxide or thallium ethoxide. Surprisingly, reaction of 1H with the Grignard reagent MeMgBr to prepare the corresponding dialkyl derivative led to the formation of the tetranuclear magnesium dimer [Mg2BrCl{NN(Me)OH}(thf)]2 {NN(Me)OH = 2-tert-butyl-6-[1-(quinolin-8-ylamido)ethyl]phenoxide} (2), whose structure was determined by single-crystal X-ray diffraction. By reacting the neutral ligand NNOH-H with Y(CH2SiMe3)3·2thf in toluene at low temperature the alkyl complex [Y(CH2SiMe3){NN(CH2SiMe3)O}(thf)] {NN(CH2Si- Me3)O = 2-tert-butyl-6-[1-(quinolin-8-ylamido)-2-trimethylsilanylethyl] phenoxide} (3) was isolated. The supposed reaction mechanism leading to the formation of 3 was simulated by using the PM6 Hamiltonian.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.