The double 1,3-dipolar cycloaddition of allenoates with nitrilimines has been achieved under mild reaction conditions, affording a variety of spirobidihydropyrazoles in moderate to excellent yields with excellent diastereoselectivities. The reaction diastereoselectively constructs double dihydropyrazole moieties and two chiral centers including a spiro carbon center.
A palladium-catalyzed three-component carbonylative reaction for the synthesis of 3H-1,2,4-triazol-3-ones from hydrazonoyl chlorides and NaN3 has been achieved. The reaction presumably proceeds through a cascadecarbonylation, acyl azide formation, Curtius rearrangement, and intramolecular nucleophilic addition sequence. A wide variety of structurally diverse 3H-1,2,4-triazol-3-ones were constructed
已实现了钯催化的三组分羰基化反应,该反应可从酰氯和NaN 3合成3 H -1,2,4-三唑-3-酮。该反应大概通过级联羰基化,酰基叠氮化物形成,Curtius重排和分子内亲核加成序列进行。以中等至优异的产率构建了各种结构多样的3 H -1,2,4-三唑-3-酮。1,2,3,5-三甲酸三苯酯(TFBen)被用作固体和方便的一氧化碳替代物。
Synthesis and Antifungal Activities of New Pyrazole Derivatives via 1,3-dipolar Cycloaddition Reaction
作者:Chuan-Yu Zhang、Xing-Hai Liu、Bao-Lei Wang、Su-Hua Wang、Zheng-Ming Li
DOI:10.1111/j.1747-0285.2010.00948.x
日期:——
A series of cycloadducts‐‐pyrazoles via 1,3‐dipolarcycloaddition reactions of generated nitrilimines with N‐(4‐chloro‐2‐fluorophenyl)maleimide were described. The novel compounds synthesized were characterized by 1H NMR, MS, and elemental analysis. The fungicidal tests showed that most of the title compounds exhibit significant fungicidal activities against Corynespora cassiicola.
通过生成的腈亚胺与N-(4-氯-2-氟代苯基)马来酰亚胺的1,3-偶极环加成反应描述了一系列环加合物-吡唑。合成的新型化合物通过1 H NMR,MS和元素分析进行表征。杀菌试验表明,大多数标题化合物对棒状杆菌都具有显着的杀菌活性。
Palladium-catalyzed oxidative carbonylation of hydrazides: synthesis of 1,3,4-oxadiazol-2(3H)-ones
A novel palladium-catalyzedoxidative carbonylation reaction was developed via the carbon monoxide insertions between the amine group and the carbonyl group to realize the intramolecular cyclization, which provides efficient access to 1,3,4-oxadiazol-2(3H)-ones with a wide range of substrates under mild conditions, resulting in good to excellent yields.
One‐pot synthesis of 2‐imino‐1,3,4‐thiadiazolines from acylhydrazides and isothiocyanates
作者:Su Been Kim、Sang Eun Baek、Jae Hyeok Lim、Jinho Kim
DOI:10.1002/bkcs.12585
日期:2022.8
A one-pot synthesis of 2-imino-1,3,4-thiadiazolines was successfully achieved under mild conditions. The developed synthesis involves Fe(Pc)-catalyzed aerobic oxidation of acylhydrazides followed by P(NMe2)3-mediated annulation of the in situ generated N-acyldiazene with isothiocyanates. The present annulation showed broad substrate scope with good functional group tolerance, and was effective on gram