The synthesis of imidazo[1,5-a]pyridines through denitrogenative transannulation of pyridotriazoles with nitriles using BF3·Et2O as catalyst has been described. The combination of solvents (dichlorobenzene-dichloroethane) plays a crucial role in achieving quantitative yields of desired products under metal-free conditions.
已经描述了使用BF 3 ·Et 2 O作为催化剂通过吡啶三唑与腈的脱氮脱环反应合成咪唑并[1,5- a ]吡啶。溶剂的组合(二氯苯-二氯乙烷)在无金属条件下获得所需产品的定量收率方面起着至关重要的作用。
Copper-Catalyzed Denitrogenative Transannulation Reaction of Pyridotriazoles: Synthesis of Imidazo[1,5-<i>a</i>]pyridines with Amines and Amino Acids
The copper-catalyzedaerobicoxidativesynthesis of imidazo[1,5-a]pyridines via cascade denitrogenative transannulation reaction of pyridotriazoles with benzylamines with good functional group tolerance is developed. The present methodology is also applicable to amino acids to obtain imidazo[1,5-a]pyridines via decarboxylative oxidative cyclization.
通过吡啶三唑与具有良好官能团耐受性的苄胺的级联脱氮环氧化反应,开发了铜催化的咪唑并[1,5- a ]吡啶的好氧氧化合成反应。本方法学也适用于氨基酸,通过脱羧氧化环化获得咪唑并[1,5- a ]吡啶。
Copper-Catalyzed Oxidative Amination of sp<sup>3</sup> C–H Bonds under Air: Synthesis of 1,3-Diarylated Imidazo[1,5-<i>a</i>]pyridines
A copper(II)-catalyzed tandem reaction between pyridine ketone and benzylamine was developed by using clean O2 as an oxidant. This transformation proceeded via an efficient condensation–amination–oxidative dehydrogenation process, affording 1,3-diarylated imidazo[1,5-a]pyridines in excellent yields.
通过使用纯净的O 2作为氧化剂,进行了吡啶酮和苄胺之间的铜(II)催化串联反应。该转化过程通过有效的缩合-胺化-氧化脱氢过程进行,从而以优异的收率得到了1,3-二芳基咪唑并[1,5- a ]吡啶。
Synthesis of Fluorescent 1,3-Diarylated Imidazo[1,5-<i>a</i>]pyridines: Oxidative Condensation−Cyclization of Aryl-2-Pyridylmethylamines and Aldehydes with Elemental Sulfur as an Oxidant
Oxidative condensation−cyclization of aldehydes and aryl-2-pyridylmethylamines proceeded in the presence of a stoichiometric amount of elemental sulfur as an oxidant in the absence of catalyst. The reaction gave a variety of 1,3-diarylated imidazo[1,5-a]pyridines in good to high yields. The products showed fluorescence emission in a wavelength range of 454−524 nm. The quantum yields of 1,3-diarylated
醛和芳基-2-吡啶基甲胺的氧化缩合环化反应在存在化学计算量的元素硫作为氧化剂且没有催化剂的情况下进行。反应以良好至高收率得到各种1,3-二芳基咪唑并[1,5- a ]吡啶。产品显示出在454-524 nm波长范围内的荧光发射。与母体3-单取代的化合物相比,1,3-二芳基咪唑并吡啶的量子产率大大提高。
Construction of Imidazole-Fused-Ring Systems by Iron-Catalyzed C(sp<sup>3</sup>)-H Amination–Cyclization under Aerobic Conditions