Accessing Polysubstituted Quinazolines via Nickel Catalyzed Acceptorless Dehydrogenative Coupling
作者:Seuli Parua、Rina Sikari、Suman Sinha、Gargi Chakraborty、Rakesh Mondal、Nanda D. Paul
DOI:10.1021/acs.joc.8b01479
日期:2018.9.21
easy to prepare nickel catalysts, containing tetraaza macrocyclic ligands (tetramethyltetraaza[14]annulene (MeTAA) or 6,15-dimethyl-8,17-diphenyltetraaza[14]annulene (MePhTAA)) are reported. A wide variety of substituted quinazolines were synthesized in moderate to high yields starting from cheap and easily available starting precursors. A few control reactions were performed to understand the mechanism
Direct synthesis of N-heterocycles via the acceptorless dehydrogenative coupling is very challenging and scarcely reported under 3d transition-metal catalysis. Here, we have developed an efficient Mn(I)-catalyzed sustainable synthesis of various quinoxalines from 1,2-diaminobenzenes and 1,2-diols via the acceptorless dehydrogenative coupling reaction. Further, this strategy was successfully applied
A facile and versatile protocol for the one-pot PhI(OAc) 2 mediated divergent synthesis of quinazolines from 2-aminobenzylamine
作者:Moumita Saha、Prasun Mukherjee、Asish R. Das
DOI:10.1016/j.tetlet.2017.04.036
日期:2017.5
be the key reagent in absence or presence of catalytic amount of molecular iodine (I2)/zinc chloride (ZnCl2) to construct quinazoline scaffold from 2-aminobenzylamine and a variety of easily available aldehydes, aryl and aliphatic amines, aliphatic and aryl alcohols and nitriles. This protocol provides mild and robust conditions along with great versatility to synthesize 2-substituted quinazolines from
been prepared by a ruthenium(II)-catalyzed direct ortho-C–H arylation of 2-(aryl/heteroaryl)-substituted quinazolines with (hetero)aryl bromides. Tri(hetero)aryl-substituted alkenes were also prepared by olefinic C–H activation of 2-(2-arylvinyl)quinazoline derivatives. High conversions and selectivities were achieved by choosing the appropriate ruthenium(II) carboxylate catalyst system, solvent, and reaction
通过钌(II)催化的2-(芳基/杂芳基)-取代的喹唑啉与(杂)芳基溴化物的直接邻-C-H芳基化反应制备了一系列偶联产物。三(杂)芳基取代的烯烃也可以通过烯烃 C-H 活化 2-(2-芳基乙烯基)喹唑啉衍生物制备。通过选择合适的羧酸钌 (II) 催化剂体系、溶剂和反应温度,实现了高转化率和选择性。还证明了通过应用芳基化/还原反应序列进行 C(sp3)-H 功能化的可能性。
Niacin as a Potent Organocatalyst towards the Synthesis of Quinazolines Using Nitriles as C-N Source
作者:Raghuram Gujjarappa、Nagaraju Vodnala、Velma Ganga Reddy、Chandi C. Malakar
DOI:10.1002/ejoc.201901651
日期:2020.2.21
An organocatalyzed protocol has been described for the comprehensive synthesis of 2‐substituted quinazolines usingnitriles as C–N source. The developed reaction conditions are suitable for a wide range of substrates providing the desired products in excellent yields.