Reactions of 4-chloro-5<i>h</i>-1,2,3-dithiazole-5-thione with α,β-unsaturated β-amino esters: Formation of 2-[2-(1-alkenylsulfanyl-1-alkoxycarbonyl-2-amino)-1,2-dicyano-vinylsulfanyl]-3-amino-2-alkenoic alkyl esters
作者:Yong-Goo Chang、Kyongtae Kim、Yung Ja Park
DOI:10.1002/jhet.5570390103
日期:2002.1
Treatment of 4-chloro-5H-1,2,3-dithiazole-5-thione with alkyl 3-alkyl (or aryl)-3-amino-2-propenoates in the presence of pyridine (2 equivalents) in dichloromethane at reflux gave 2-[2-(1-alkenylsulfanyl-1-alkoxy-carbonyl-2-amino)-1,2-dicyanovinylsulfanyl]-4 and-1,2-dicyanovinyldisulfanyl]-3-amino-2-alkenoicalkylesters 7 in 16 to 60% and 8 to 48% yields, respectively.
在吡啶(2当量)在二氯甲烷中回流下,用3-烷基(或芳基)-3-氨基-2-丙烯酸烷基酯处理4-氯-5 H -1,2,3-二噻唑-5-硫酮得到2- [2-(1- alkenylsulfanyl-1-烷氧基羰基-2-氨基)-1,2- dicyanovinylsulfanyl] - 4和-1,2- dicyanovinyldisulfanyl] -3-氨基-2-链烯酸烷基酯7在产率分别为16%至60%和8%至48%。
Trifluoroethanol as a Unique Additive for the Chemoselective Electrooxidation of Enamines to Access Unsymmetrically Substituted NH‐Pyrroles
作者:Mrinmay Baidya、Debabrata Maiti、Lisa Roy、Suman De Sarkar
DOI:10.1002/anie.202111679
日期:2022.1.26
A chemoselective electrooxidative heterocoupling of two different enamines is reported for the synthesis of unsymmetricallysubstituted NH-pyrroles. A “magic effect” of the additive trifluoroethanol is utilized to achieve the desired chemoselectivity by tuning the oxidation potentials and controlling the activation energy of the rate-determining step.
Reactivity of<i>p</i>-phenyl substituted β-enamino compounds using k-10/ultrasound. I. synthesis of pyrazoles and pyrazolinones
作者:Claudete J. Valduga、Hugo S. Braibante、Mara E. F. Braibante
DOI:10.1002/jhet.5570350136
日期:1998.1
The reactivity of the β-enamino ketones, 3-amino-1-(p-phenyl-substituted)-2-buten-1-ones 1a-d and β-enamino esters. Ethyl-3-amino-3-(p-phenyl-substituted)-2-propenoates 5a-d were evaluated by systematic studies of the reactions with hydrazine and methylhydrazine by reactions with solid support K-10/ultrasound and homogeneous media (reflux in ethanol or dichloromethane) yielding pyrazole rings 2a-d
Reactivity of<i>p</i>-phenyl substituted β-enamino compounds using K-10/ultrasound.<b>I</b>. Synthesis of pyrazoles and pyrazolinones
作者:Claudete J. Valduga、Hugo S. Braibante、Mara E. F. Braibante
DOI:10.1002/jhet.5570340513
日期:1997.9
The reactivity of the β-enamino ketones, 3-amino-1-(p-phenyl-substituted)-2-buten-1-ones 1a-d and β-enamino esters, ethyl 3-amino-3-(p-phenyl-substituted)-2-propenoates 5a-d was systematically studied when allowed to react with hydrazine and methylhydrazine under solid support K-10/ultrasound conditions and in homogeneous media (reflux in ethanol or dichloromethane). The products were pyrazoles 2a-d
arylboronic acids and ester (Z)-3-aminoacrylates, one-pot syntheses of diverse indole-3-carboxylic esters have been described through copper(II)-catalyzed sequential Chan–Lam N-arylation and cross-dehydrogenativecoupling (CDC) reactions. The initial Chan–Lam arylation can proceed in DMF at 100 °C for 24 h to give ester (Z)-3-(arylamino)acrylate intermediates in the presence of Cu(OAc)2/tri-tert-butylphosphine
从芳基硼酸和酯 ( Z )-3-氨基丙烯酸酯开始,通过铜 ( II ) 催化的顺序 Chan-Lam N-芳基化和交叉脱氢偶联 (CDC )描述了多种吲哚-3-羧酸酯的一锅合成。) 反应。最初的 Chan-Lam 芳基化可以在 DMF 中在 100 °C 下进行 24 小时,在 Cu(OAc) 2 /三叔丁基膦四氟硼酸催化剂存在下得到酯 ( Z )-3-(芳氨基)丙烯酸酯中间体。作为添加剂的肉豆蔻酸、KMnO 4和KHCO 3的量。依次,这些就地芳基化中间体可以在混合溶剂(DMF/DMSO = 2:1)中在 130 °C 下进行分子内氧化交叉脱氢偶联过程,得到 C3 官能化多取代吲哚衍生物。