78386-71-7Relevant academic research and scientific papers
I2/K2S2O8 Mediated Direct Oxidative Annulation of Alkylazaarenes with Amidines for the Synthesis of Substituted 1,3,5-Triazines
Zhang, Jun,Zheng, Tingting,Zhang, Jidong
supporting information, p. 860 - 865 (2020/02/20)
A direct method for the synthesis of heteroaryl-substituted 1,3,5-triazines from readily available methyl-azaarenes and amidines has been developed. The present method involves iodine mediated cascade aerobic C(sp3)–H oxidative amination and following condensation, cyclization with amidine. Both of methyl quinoline, pyridine and benzothiazole derivatives could be well tolerated to react with various amidines leading to corresponding products in good to excellent yields.
Synthesis, characterization, and cycloaddition reactivity of a monocyclic aromatic 1,2,3,5-tetrazine
Wu, Zhi-Chen,Boger, Dale L.
, p. 16388 - 16397 (2019/10/16)
Herein we disclose the synthesis and full characterization of the first monocyclic aromatic 1,2,3,5-tetrazine, 4,6-diphenyl-1,2,3,5-tetrazine. Initial studies of its cycloaddition reactivity, mode, regioselectivity, and scope illustrate that it participates as the 4π-component of well-behaved inverse electron demand Diels-Alder reactions where it preferentially reacts with electron-rich or strained dienophiles. It was found to exhibit an intrinsic reactivity comparable to that of the isomeric 3,6-diphenyl-1,2,4,5-tetrazine, display a single mode of cycloaddition with reaction only across C4/N1 (no N2/N5 cycloaddition observed), proceed with a predictable regioselectivity (dienophile most electron-rich atom attaches to C4), and manifest additional reactivity complementary to the isomeric 1,2,4,5-tetrazines. It not only exhibits a remarkable cycloaddition reactivity, surprisingly good stability (e.g., stable to chromatography, long-term storage, presence of H2O even as reaction co-solvent), and broad cycloaddition scope, but it also displays powerful orthogonal reactivity with the 1,2,4,5-tetrazines. Whereas the latter reacts at extraordinary cycloaddition rates with strained dienophiles (tetrazine ligation), the new and isomeric 1,2,3,5-tetrazine displays similarly remarkable cycloaddition rates and efficiencies with amidines (1,2,3,5-tetrazine/amidine ligation). The crossover reactivities (1,2,4,5-tetrazines with amidines and 1,2,3,5-tetrazines with strained dienophiles) are sufficiently low to indicate they may be capable of use concurrently without competitive reactions.
IEDDA Reaction of the Molecular Iodine-Catalyzed Synthesis of 1,3,5-Triazines via Functionalization of the sp3 C-H Bond of Acetophenones with Amidines: An Experimental Investigation and DFT Study
Tiwari, Abhishek R.,Nath, Shilpa R.,Joshi, Kaustubh A.,Bhanage, Bhalchandra M.
, p. 13239 - 13249 (2017/12/26)
The present work reports an inverse electron demand Diels-Alder (iEDDA)-type reaction to synthesize 1,3,5-trizines from acetophenones and amidines. The use of molecular iodine in a catalytic amount facilitates the functionalization of the sp3 C-H bond of acetophenones. This is a simple and efficient methodology for the synthesis of 1,3,5-triazines in good to excellent yields under transition-metal-free and peroxide-free conditions. The reaction is believed to take place via an in situ iodination-based oxidative elimination of formaldehyde. DFT calculations at the M062X/6-31+G(d,p) level were employed to investigate the reaction mechanism. Reaction barriers for the cycloaddition as well as a formaldehyde expulsion steps were computed, and a multistep mechanism starting with the nucleophilic attack by benzamidine on an in situ generated imine intermediate has been proposed. Both local and global reactivity descriptors were used to study the regioselectivity of the addition steps.
Polythene glycol (PEG) as a reusable solvent system for the synthesis of 1,3,5-triazines via aerobic oxidative tandem cyclization of benzylamines and N-substituted benzylamines with amidines under transition metal-free conditions
Tiwari, Abhishek R.,Bhanage, Bhalchandra M.
supporting information, p. 144 - 149 (2015/12/31)
A green and highly efficient protocol for the synthesis of 1,3,5-triazines from benzylamines and N-substituted benzylamines with amidines in PEG-600 has been developed. This protocol is transition-metal free, phosphine ligand free and uses inexpensive, easily available molecular oxygen (O2) as an oxidant. A series of 1,3,5-triazines derivatives were synthesized in good to excellent yields in a shorter reaction time. The ease of the product separation and reusability of PEG-600 makes it more environmentally benign and economically affordable for gram-scale synthesis.
Iridium-catalyzed cascade dehydrogenation, ring-closure reaction leading to 2,4,6-triaryl-1,3,5-triazines
Shi, Gang,He, Fei,Che, Youxin,Ni, Caihua,Li, Ying
, p. 380 - 386 (2016/04/20)
An efficient iridium-catalyzed dehydrogenation, ring-closure reaction, has been developed via a cascade sequence, in which [Cp?IrI2]2/Xantphos proved to be the most efficient catalyst for the synthesis of 2,4,6-triaryl-1,3,5-triazines from stable aryl-substituted alcohols and amidines. It was the first case of iridium catalyst successful application in such transformation.
Synthesis of 1,3,5-triazines via Cu(OAc)2-catalyzed aerobic oxidative coupling of alcohols and amidine hydrochlorides
You, Qing,Wang, Fei,Wu, Chaoting,Shi, Tianchao,Min, Dewen,Chen, Huajun,Zhang, Wu
supporting information, p. 6723 - 6727 (2015/06/25)
Cu(OAc)2 was found to be an efficient catalyst for dehydrogenative synthesis of 1,3,5-triazine derivatives via oxidative coupling reaction of amidine hydrochlorides and alcohols in air. Both aromatic and aliphatic alcohols can be involved in the reaction and thirty-three products were obtained with good to excellent yields. Moreover, the use of a ligand, strong base and organic oxidant is unnecessary.
NIS-catalyzed oxidative cyclization of alcohols with amidines: A simple and efficient transition-metal free method for the synthesis of 1,3,5-triazines
Tiwari, Abhishek R.,Akash,Bhanage, Bhalchandra M.
supporting information, p. 10973 - 10976 (2015/11/25)
An efficient method for the synthesis of 1,3,5-triazines by NIS-catalyzed oxidative cyclization of alcohols with amidines has been developed. The reaction works smoothly under transition-metal free and phosphine-free conditions to afford a wide range of 1,3,5-triazine derivatives in moderate to good yields. The synthetic methodology was achieved via in situ oxidation of alcohols to aldehydes.
An efficient ruthenium-catalyzed dehydrogenative synthesis of 2,4,6-triaryl-1,3,5-triazines from aryl methanols and amidines
Xie, Feng,Chen, Mengmeng,Wang, Xiaoting,Jiang, Huanfeng,Zhang, Min
supporting information, p. 2761 - 2768 (2014/05/06)
By using [RuCl2(p-Cymene)]2/Cs2CO 3 as an efficient catalyst system, the readily available, inexpensive aryl methanols were firstly employed for dehydrogenative synthesis of aryl substituted 1,3,5-triazine derivatives. Due to the inherent stability of alcohols in contrast with aldehydes, our synthetic protocol is adaptable to a broad substrate scope, there is no need for stringent protection during the whole operation process, and it has the potential to prepare valuable products that are currently inaccessible or challenging to prepare using conventional methods. It is a significantly important complement to the conventional synthetic methodologies. This journal is the Partner Organisations 2014.
DIELS-ALDER REACTIONS WITH INVERSE ELECTRON DEMAND. II. THE REACTION OF BENZAMIDINE WITH ?-DEFICIENT HETEROAROMATIC COMPOUNDS
Figeys, H. P.,Mathy, A.
, p. 1393 - 1396 (2007/10/02)
Benzamidine (I) reacts with several s-tetrazines to give as-triazines in moderate to good yield, together with some s-triazines; separate experiments have shown that these are due to the fact that (I) also undergoes Diels-Alder-reactions with as- and even with s-triazines.
