本研究提倡对两种化学式为C 23 H 18 F 2 N 4 O(5a)和C 25 H 22 FN 5 O 3(5b)的苯并咪唑基强azo进行联合实验和计算研究。两个图5a和5b中的合成和拆分成使用SC-XRD为键长,键角,单元电池和空间群的评估它们的晶体结构。5a和5b的结构使用红外(FT-IR),UV-可见,核磁共振进行化学表征(1H-NMR和13 C-NMR),EIMS和元素分析。在M06-2X / 6-31G(d,p)的理论水平上进行了DFT,以获得优化的结构并反驳了实验结果。总的来说,DFT的发现与实验数据非常吻合,证实了这两种化合物的纯度。在相同的理论水平上探索了FMO,NBO分析,MEP表面和非线性光学(NLO)特性。在TDDFT / M06-2X / 6-31G(d,p)的理论水平UV-Vis分析表明,图5b是红色的移λ最大331.69纳米相比,图5a与λ最大240.25纳米
Diversity-oriented synthesis of imidazo[2,1-<i>a</i>]isoquinolines
作者:Shaoyu Mai、Yixin Luo、Xianyun Huang、Zhenghao Shu、Bingnan Li、Yu Lan、Qiuling Song
DOI:10.1039/c8cc05390a
日期:——
Herein, we report an efficient and practical strategy for the synthesis of five types of imidazo[2,1-a]isoquinolines via Cp*RhIII-catalyzed [4+2] annulation of 2-arylimidazoles and α-diazoketoesters, whose structural and substituted diversity at 5- or 6-position can be precisely controlled by the α-diazoketoester coupling partners. Compared with previous reports, in this study, we merged two attractive
本文中,我们报告了通过Cp * Rh III催化的2-芳基咪唑和α-重氮酮酸酯的[4 + 2]环合反应合成五种咪唑并[ 2,1- a ]异喹啉的有效而实用的策略。可以通过α-重氮酮酸酯偶合伙伴精确控制5位或6位取代的多样性。与以前的报告相比,在这项研究中,我们通过选择合适的酯基团(–COOEt,–COO tBu或–COOiPr)或廉价的添加剂(HOAc或KOAc)。此外,通过几种生物活性化合物的简明合成和代表性药物的后期修饰,证明了这些方法的合成功效。
An efficient NaHSO3-promoted protocol for chemoselective synthesis of 2-substituted benzimidazoles in water
NaHSO3 was more than 11 equivalents, the 2-substituted benzimidazole could be highly selectively formed as the sole product. NaHSO3 was firstly reacted with aldehyde to form the aldehyde sodium bisulfite, which reacted with o-phenylenediamine to form the 2-substituted benzimidazole and inhibited the formation of 1,2-disubstituted benzimidazole. This protocol solved the poor selectivity problem appearing
Nickel catalysed construction of benzazoles <i>via</i> hydrogen atom transfer reactions
作者:Amreen K. Bains、Dhananjay Dey、Sudha Yadav、Abhishek Kundu、Debashis Adhikari
DOI:10.1039/d0cy00748j
日期:——
Herein we report a homogeneous, phosphine free, inexpensive nickel catalyst that forms a wide variety of benzazoles from alcohol and diamines by a reaction sequence of alcohol oxidation, imine formation, ring cyclization and dehydrogenative aromatization. A reversible azo/hydrazo couple, that is part of the ligand architecture steers both the alcohol oxidation and dehydrogenation of the annulated amine
efficient and convenient Ni-catalyzed C–N bond formation for the synthesis of various benzimidazoles from various 2-haloanilines, aldehydes, and ammonia in a concise manner is reported. This protocol uses commercially available, nonhazardous, clean ammonia as a reaction partner instead of other nitrogen sources. Benzimidazoles, as the sole products, were obtained in high to excellent yields (up to 95%)
报道了一种高效且方便的 Ni 催化 C-N 键形成,用于以简洁的方式从各种 2-卤代苯胺、醛和氨合成各种苯并咪唑。该协议使用市售的、无害的、清洁的氨作为反应伙伴,而不是其他氮源。苯并咪唑作为唯一的产品,以高到极好的收率(高达 95%)获得。
Base-mediated synthesis of benzimidazole-fused 1,4-benzoxazepines via sequential intermolecular epoxide ring-opening/intramolecular SNAr reactions
作者:Runjun Devi、Subhamoy Mukhopadhyay、Arup Jyoti Das、Sajal Kumar Das
DOI:10.1016/j.tetlet.2020.152491
日期:2020.11
intramolecular nucleophilic aromatic substitution (SNAr) reaction of the resulting products in the presence of NaH. We have also achieved an 11-step synthesis of a chroman-linked benzimidazole-fused 1,4-benzoxazepine using a phenoxide-ion induced 6-exo intramolecular epoxide ring-opening and an alkoxide-ion induced intramolecular SNAr reaction as key steps.
我们已经开发出一种无过渡金属的实用方法,可制得苯并咪唑稠合的1,4-苯并x氮平。在操作上,该协议涉及A K 2 CO 3介导的通过2-(2-氟苯基)苯并咪唑末端环氧化物的分子间开环,随后通过分子内亲核芳族取代(S Ñ AR)所得产物的反应在NaH存在下。我们还利用苯酚离子诱导的6- exo分子内环氧化物开环和醇盐离子诱导的分子内S N Ar反应作为关键步骤,完成了由苯并咪唑键合的苯并咪唑稠合的1,4-苯并氮杂ze庚烷的11步合成。