共查询到19条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
5.
N-三甲基硅甲基苄胺和多聚甲醛在磷酸催化下生成非稳定型亚甲胺基叶立德,继而与各种贫电子烯烃在温和条件下发生三组分1,3-偶极环加成反应,高收率合成了10个3,4-二取代四氢吡咯衍生物(其中6个为新化合物),其结构经1H NMR,13C NMR和HR-MS表征。 相似文献
6.
7.
1,3—偶极环加成反应在杂螺环化合物合成中的应用 总被引:1,自引:0,他引:1
氧化腈与4,4-亚甲基-1-甲基哌啶的1,3-偶极环加成反应生成了杂螺[4.5]葵烷化合物,反应具有立体专一性.产物经LiAlH4还原生成了γ-氨基醇,最后经插入C-1单元扩环生成了新的杂螺[5.5]十一烷化合物 相似文献
8.
利用1,3-偶极环加成反应对卟啉大环进行修饰是近年来卟啉研究的一个新热点。环加成产物因在可见光谱长波段范围的特征吸收,在构筑人工光反应体系和用作光动力疗法中的光敏剂等领域有重要应用价值。本文综述了1,3-偶极环加成反应在修饰卟啉化合物方面的研究进展,包括:卟啉作为亲偶极体能与甲亚胺叶立德、硝酮、重氮烷、羰基叶立德、腈氧化物等1,3-偶极子反应生成各种新型杂环稠合卟吩类化合物;卟啉化合物作为1,3-偶极子能与C60等亲偶极体反应,生成β位取代的各种新型卟啉化合物;以及扩展卟啉也可以作为亲偶极体与甲亚胺偶极子发生1,3-偶极环加成反应等。 相似文献
9.
利用微波促进氮杂糖硝酮(2)与丙烯酸类衍生物(3)发生1,3-偶极环加成反应,立体选择性地得到了一系列新的含异噁唑烷的氮杂糖衍生物(4),反应效率显著提高,反应时间由95h缩短为5~15min,收率由67%提高到78%~88%.利用NMR和HRMS等方法结合化合物(4d-1)的单晶结构确定了产物的结构和相对构型. 相似文献
10.
Cu(I)催化的亚甲胺叶立德和亚环丙基乙酸乙酯参与的不对称endo-1,3-偶极环加成反应,高效构建了多官能化、含有多个连续季碳中心的5-氮杂-[2,4]庚烷化合物.此反应具有广泛的底物适用性,α-取代的和α-非取代的亚甲胺叶立德和亚环丙基乙酸乙酯都能很好的参与反应,并以很高的产率、优秀的非对映选择性(95:5–98:2 d.r)和对映选择性(87%–98%ee)生成相应的在2,3,4位上含有连续季碳中心的螺四氢吡咯化合物. 相似文献
11.
Li Xiaofang Liu Bin Liu Haochong Yu Xianyong Yi Pinggui 《Journal of heterocyclic chemistry》2012,49(5):1050-1053
The 1,3‐dipolar cycloaddition of azomethine ylide generated in situ from isatin and sarcosine to 5‐arylmethylidene thiazolo[3,2‐b][1,2,4]triazol‐6(5H)‐ones afforded novel 1′‐methyl‐4′‐aryldispiro[indole‐3,2′‐pyrrolidine‐3′,5″‐[1,3]thiazolo[3,2‐b][1,2,4]triazole]‐2,6″ (1H)‐diones in moderate yields. The structures of all the products were characterized thoroughly by NMR, infrared spectroscopy (IR), mass spectroscopy (MS) elemental analysis together with X‐ray crystallographic analysis. 相似文献
12.
Li Xiaofang Liu Haochong Zheng Aiting Li Zhikui Li Guobin Yu Xianyong Yi Pinggui 《中国化学》2011,29(1):97-101
The 1,3‐dipolar cycloaddition of an azomethine ylide generated by a decarboxylative route from sarcosine and acenaphthenequinone to 7‐arylmethylidene‐3‐aryl‐3,4‐dihydro‐2H‐thiazolo[3,2‐a][1,3,5]triazin‐6(7H)‐ones afforded novel dispiro[acenaphthylene‐1,2′‐pyrrolidine]‐3′,7′ ′‐[1,3]thiazolo[3,2‐a][1,3,5]triazines in moderate yields. The structures of the products were determined and characterized thoroughly by NMR, MS, IR, elemental analysis and X‐ray crystallographic analysis. The results of experiment indicated that this 1,3‐dipolar cycloaddition proceeded with high stereoselectivity and regioselectivity. 相似文献
13.
The 1,3‐dipolar cycloaddition of azomethine ylides derived from isatin and amino acids viz. sarcosine and proline to 2‐arylmethylidene‐5,6‐dihydroimidazo[2,1‐b]thiazol‐3(2H)‐ones afforded novel spiro pyrrolidines and pyrrolizidines regio‐ and stereoselectively in moderate yields. The products were characterized thoroughly by IR, MS, NMR together with elementary analysis. 相似文献
14.
Russian Journal of Organic Chemistry - Three-component 1,3-dipolar cycloaddition reactions between isatin, benzylamine, and α,β-unsaturated ketones at room temperature afforded... 相似文献
15.
Oleksandr S. Liashuk Ihor A. Ryzhov Dr. Oleksandr V. Hryshchuk Bohdan V. Vashchenko Pavlo V. Melnychuk Prof. Dr. Yulian M. Volovenko Prof. Dr. Oleksandr O. Grygorenko 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(54):e202202117
A scalable and efficient process for the preparation of 3-borylated pyrrolidines by 1,3-dipolar cycloaddition of N-benzyl azomethine ylide generated in situ has been developed. The optimized method included the use of LiF in DMSO at 110 °C and was suitable for α-mono-, α,β-di-, and α,β,β-trialkyl-, β,β-(hetera)cycloalkylidene-, CO2Et-, as well as most β-(het)aryl-substituted alkenyl boropinacolates. The 1,3-dipolar reaction proceeded on a multigram scale providing 3-borylated pyrrolidines with diverse substitution patterns (including fused and spirocyclic ones) in a diastereoselective manner. The Pd(OH)2-mediated N-debenzylation of pyrrolidine hydrochlorides was successfully performed to give the corresponding bifunctional building blocks on an up to 130 g scale, thus providing a substantial expansion of the synthetic and medicinal chemist's toolbox. Other reactions included the preparation of trifluoroborates, Zweifel-Aggarwal sp3-sp2 coupling, and oxidative deborylation as an example of C-heteroatom bond formation. 相似文献
16.
17.
The 1,3‐dipolar cycloaddition of an azomethine ylide generated by a decarboxylative route from sarcosine and isatin to 1‐benzyl‐3,5‐diarylmethylidene‐piperidin‐4‐ones afforded novel di‐spiro‐indolo/pyrrolidino/piperidines in moderate yields. Further cycloaddition of these di‐spiro compounds to nitrile oxide afforded tri‐spiro‐indolo/pyrrolidino/piperadino/isoxazolines in moderate yields with high regio‐ and stereoselectivity. 相似文献
18.
19.
Moroz A. A. Dmitriev M. V. Maslivets A. N. 《Russian Journal of Organic Chemistry》2020,56(7):1166-1173
Russian Journal of Organic Chemistry - The Knoevenagel condensation of 1H-pyrrole-2,3-diones with malononitrile gave 3-(dicyanomethylidene)-2,3-dihydro-1H-pyrrole-2-ones which were brought into... 相似文献