77629-84-6Relevant academic research and scientific papers
Pd-catalyzed divergent C(sp2)-H Activation/Cycloimidoylation of 2-Isocyano-2,3-diarylpropanoates
Tang, Shi,Yang, Sheng-Wen,Sun, Hongwei,Zhou, Yali,Li, Juan,Zhu, Qiang
, p. 1832 - 1836 (2018)
A Pd-catalyzed site-selective C(sp2)-H activation/cycloimidoylation of 2-isocyano-2,3-diarylpropanoates to construct diverse cyclic imine products has been developed. Six-membered 3,4-dihydroisoquinolines containing a C3 quaternary carbon cente
Boron-Catalyzed Azide Insertion of α-Aryl α-Diazoesters
San, Htet Htet,Wang, Chun-Ying,Zeng, Hai-Peng,Fu, Shi-Tao,Tang, Xiang-Ying,Jiang, Min
, p. 4478 - 4485 (2019/05/01)
A challenging metal-free azide insertion of α-aryl α-diazoesters in the presence of B(C6F5)3 (5 mol %) was developed for the first time. The reaction features an easy operation, wide substrate scope, and mild conditions an
Synthesis ofα-azido ketones and esters using recyclable hypervalent iodine reagent
Telvekar, Vikas N.,Patile, Hemlata V.
experimental part, p. 131 - 135 (2011/02/27)
A simple and mild method for the preparation of αazido ketones and esters using hypervalent iodine reagent, 4,4'-bis-(dichloroiodo)-biphenyl, and sodium azide in 1,4-dioxane is discussed. Advantages of this system are easy workup, recyclable reagent, and
Diastereochemical diversity of imidazoline scaffolds via substrate controlled TMSCI mediated cycloaddition of azlactones
Sharma, Vasudha,Tepe, Jetze J.
, p. 5091 - 5094 (2007/10/03)
(Chemical Equation Presented) We report herein a trimethylsilyl chloride mediated substrate controlled 1,3-dipolar cycloaddition for the diastereoselective synthesis of either syn- or anti-imidazolines. This method provides scaffolds with four points of diversity and control over two stereocenters.
The Effects of α-Substituents on the Kinetic and Thermodynamic Stability of 4-Methoxybenzyl Carbocations: Carbocation Lifetimes That Are Independent of Their Thermodynamic Stability
Amyes, Tina L.,Stevens, Ishmael W.,Richard, John P.
, p. 6057 - 6066 (2007/10/02)
The following new rate constants for reaction of α-substituted 4-methoxybenzyl carbocations, 4-MeOC6H4CR1(R2)(1+), with a solvent of 50:50 (v/v) trifluoroethanol/water at 25 deg C and ionic strength 0.50 (NaClO4) are reported: 4-MeOC6H4CH(OMe)(1+), Ks = 2.2E7 s-1; 4-MeOC6H4CH(N3)(1+), ks = 3.3E5 s-1; 4-MeOC6H4C(CH3)2(1+), ks = 1.3E7 s-1; 4-MeOC6H4CH(CO2Et)(1+), ks = 1.4E7 s-1; 4-MeOC6H4CCH3(CF3)(1+), ks = 2.5E7 s-1.The values of ks for reaction of 4-MeOC6H4CR1(R2)(1+) with 50:50 (v/v) trifluoroethanol/water are nearly independent of very large changes in the thermodynamic stability of these carbocations caused by the addition of a wide range of electron-withdrawing or electron-donating groups at the α-position.In the most extreme case, the change from an α-methoxy to two α-(trifluoromethyl) substituents leads to a 23 kcal/mol thermodynamic destabilization of 4-MeOC6H4CR1(R2)(1+) relative to the neutral azide ion adducts but a 5-fold decrease in its reactivity toward solvent.The data show that the effects of α-substituents on the kinetic stability of 4-MeOC6H4CR1(R2)(1+) are complex and do not parallel the thermodynamic stability of these carbocations.The results are explained by consideration of the polar and resonance effects of the α-substituents on both the thermodynamic driving force and the intrinsic barrier for capture of the carbocations by solvent.These reactions are a new example of the consequences of the "principle of nonperfect synchronization".
