160290-42-6Relevant articles and documents
Molecular Engineering of Mechanochromic Materials by Programmed C-H Arylation: Making a Counterpoint in the Chromism Trend
Wu, Jie,Cheng, Yangyang,Lan, Jingbo,Wu, Di,Qian, Shengyou,Yan, Lipeng,He, Zhen,Li, Xiaoyu,Wang, Kai,Zou, Bo,You, Jingsong
, p. 12803 - 12812 (2016)
The development of facile methods for screening organic functional molecules through C-H bond activation is a revolutionary trend in materials research. The prediction of mechanochromism as well as mechanochromic trends of luminogens is an appealing yet challenging puzzle. Here, we present a strategy for the design of mechanochromic luminogens based on the dipole moment of donor-acceptor molecules. For this purpose, a highly efficient route to 2,7-diaryl-[1,2,4]triazolo[1,5-a]pyrimidines (2,7-diaryl-TAPs) has been established through programmed C-H arylation, which unlocks a great opportunity to rapidly assemble a library of fluorophores for the discovery of mechanochromic regularity. Molecular dipole moment can be employed to explain and further predict the mechanochromic trends. The 2,7-diaryl-TAPs with electron-donating groups on the 2-aryl and electron-withdrawing groups on the 7-aryl possess a relatively small dipole moment and exhibit a red-shifted mechanochromism. When the two aryls are interchanged, the resulting luminogens have a relatively large dipole moment and display a blue-shifted mechanochromism. Seven pairs of isomers with opposite mechanochromic trends are presented as illustrative examples. The aryl-interchanged congeners with a bidirectional emission shift are structurally similar, which provides an avenue for understanding in-depth the mechanochromic mechanism.
Vinylation of α-Aminoazoles with Triethylamine: A General Strategy to Construct Azolo[1,5-a]pyrimidines with a Nonsubstituted Ethylidene Fragment
Gao, Qinghe,Sun, Zhenhua,Xia, Qinfei,Li, Ruonan,Wang, Wenlong,Ma, Siwei,Chai, Yixin,Wu, Manman,Hu, Wei,ábrányi-Balogh, Péter,Keserü, Gy?rgy M.,Han, Xinya
supporting information, p. 2664 - 2669 (2021/04/12)
A new general synthesis of pharmaceutically important azolo[1,5-a]pyrimidines starting from widely available 3(5)-aminoazoles, aldehydes, and triethylamine is developed. The key is to enable the vinylation reaction that allows the in situ generation of elusive acyclic enamines and the subsequent annulation reaction to occur. This direct and practical strategy is capable of constructing a range of 5,6-unsubstituted pyrazolo[1,5-a]pyrimidines and [1,2,4]triazolo[1,5-a]pyrimidines. More importantly, this protocol provides a concise synthetic route to prepare the clinically used zaleplon.
Synthesis method of [1, 2, 4] triazolo [1, 5-a] pyrimidine compound
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Paragraph 0015-0017, (2021/05/12)
The invention discloses a synthesis method of a [1, 2, 4] triazolo [1, 5-a] pyrimidine compound, and belongs to the technical field of organic synthesis. According to the technical scheme, the preparation method is characterized by comprising the following steps: dissolving an aldehyde compound, a 3-amino-1, 2, 4-triazole compound and triethylamine in a solvent toluene, then adding ammonium iodide and di-tert-butyl peroxide, and then reacting at 130 DEG C to prepare the target product [1, 2, 4] triazole [1, 5-a] pyrimidine compound. The synthesis process is simple and efficient, the [1, 2, 4] triazolo [1, 5-a] pyrimidine compound is directly prepared in one step through the one-pot cascade reaction without transition metal catalysis, the synthesis process is convenient to operate, the raw materials are simple, the reaction conditions are mild, the yield is high, the method has a very good application prospect, and meanwhile, the production cost is greatly reduced by taking triethylamine as the raw material.
Studies with Enaminones: The reaction of enaminones with Aminoheterocycles. A route to Azolopyrimidines, Azolopyridines and Quinolines
Almazroa, Sarah,Elnagdi, Mohamed H.,Salah El-Din, Abdellatif M.
, p. 267 - 272 (2007/10/03)
The enaminones 1b,d,f react with 4-phenyl-3-methyl-5-pyrazoleamine 3a to yield the pyrazole derivatives 4a-c that cyclised readily on reflux in pyridine solution in presence of hydrochloric acid to yield the pyrazolo[1,5-a]pyrimidines 5a-c. Similarly 3(5)
The application of unsymmetrical vinylogous iminium salts and related synthons to the preparation of monosubstituted triazolo[1,5-a]pyrimidines
Petrich,Qian,Santiago,Gupton,Sikorski
, p. 12113 - 12124 (2007/10/02)
The reaction of vinylogous iminium salts and related analogs with 3-amino-1,2,4-triazole to yield 7-substituted and 5-substituted triazolo[1,5-a]pyrimidines is described.
