29554-82-3Relevant academic research and scientific papers
Versatile reactivity of scorpionate-anchored yttrium-dialkyl complexes towards unsaturated substrates
Yi, Weiyin,Zhang, Jie,Zhang, Fangjun,Zhang, Yin,Chen, Zhenxia,Zhou, Xigeng
, p. 11975 - 11983 (2013)
A series of unusual chemical-bond transformations were observed in the reactions of high active yttrium-dialkyl complexes with unsaturated small molecules. The reaction of scorpionate-anchored yttrium-dibenzyl complex [TpMe2Y(CH2Ph)2(thf)] (1, Tp Me2=tri(3,5-dimethylpyrazolyl)borate) with phenyl isothiocyanate led to C=S bond cleavage to give a cubane-type yttrium-sulfur cluster, {Tp Me2Y(μ3-S)}4 (2), accompanied by the elimination of PhN=C(CH2Ph)2. However, compound 1 reacted with phenyl isocyanate to afford a C(sp3)-H activation product, [TpMe2Y(thf){μ-η1:η3-OC(CHPh)NPh} {μ-η3:η2-OC(CHPh)NPh}YTpMe2] (3). Moreover, compound 1 reacted with phenylacetonitrile at room temperature to produce γ-deprotonation product [(TpMe2)2Y] +[TpMe2Y(N=C=CHPh)3]- (6), in which the newly formed N=C=CHPh ligands bound to the metal through the terminal nitrogen atoms. When this reaction was carried out in toluene at 120 °C, it gave a tandem γ-deprotonation/insertion/partial-TpMe2- degradation product, [(TpMe2Y)2(μ-Pz) 2{μ-η1:η3-NC(CH2Ph)CHPh}] (7, Pz=3,5-dimethylpyrazolyl).
Copper-Catalyzed Cascade Cycloamination of α-Csp3-H Bond of N-Aryl Ketimines with Azides: Access to Quinoxalines
Chen, Tengfei,Chen, Xun,Wei, Jun,Lin, Dongen,Xie, Ying,Zeng, Wei
supporting information, p. 2078 - 2081 (2016/06/01)
A copper-catalyzed cycloamination of α-Csp3-H bond of N-aryl ketimines with sodium azide has been developed. This methodology provides an efficient access to quinoxalines and features mild reaction conditions and readily available ketimines with diverse functional group tolerance.
Azomethines, 1-Azaallyl Anions, and Metastable Secondary Enamines
Knorr, Rudolf,Weiss, Alfons,Loew, Peter,Raepple, Edith
, p. 2462 - 2489 (2007/10/02)
E/Z equilibrium constants of the ketone anils 6a-s do not depend significantly on the inductive substituent effect. 1H NMR chemical shifts used for configurational classification are also effective for assignments in comparable, isomerically almost pure azomethines 6aa-pp and may be explained by the anisotropic shift model.The 1-azaallyl anions 7 prepared by deprotonation are characterized by 1H NMR spectroscopy.Kinetic and thermodynamic control of this metallation reaction result in different preferential configurations of such anions, the methanolysis of which yields metastable sec. enamines 8 by regio- and stereospecific N-protonation.It is possible to estimate further substituent parameters λd from E/Z equilibria.
