Michael additions of dihydropyrimidines and 2-amino-1,3,4-thiadiazoles to α,β-ethylenic compounds: using polyethylene glycols as a green reaction media
作者:Xicun Wang、Zhengjun Quan、Zhang Zhang
DOI:10.1016/j.tet.2007.05.108
日期:2007.8
Polyethylene glycol (PEG) was found to be an inexpensive, non-toxic, and effective medium for the Michael additions of 3,4-dihydropyrimidines to α,β-ethylenic compounds to provide N3-functionalized dihydropyrimidines in the presence of K2CO3 as the catalyst. Under similar reaction conditions, 2-amino-5-aryloxymethyl-1,3,4-thiadiazoles reacted with methyl acrylate to give unexpected products 5H,6H-[1
发现聚乙二醇(PEG)是廉价的,无毒且有效的介质,用于在K 2 CO存在下将3,4-二氢嘧啶迈克尔加成至α,β-烯键化合物以提供N 3-官能化的二氢嘧啶3作为催化剂。在相似的反应条件下,2-氨基-5-芳氧基甲基-1,3,4-噻二唑与丙烯酸甲酯反应生成意外的产物5 H,6 H- [1,3,4]噻二唑并[1,2- a ]嘧啶通过串联迈克尔加成反应和分子内环化反应得到-7-ones。
One-Pot Synthesis of Phenylallyl Substituted Unsymmetrical Ureas Under Microwave Irradiation
作者:Lan-Qin Chai、Wei-Peng Chen、Xiao-Qiang Wang、Jian-Lin Ge
DOI:10.1080/10426500701407441
日期:2007.9.13
unsymmetrical ureas were synthesized in a one-pot procedure by reactions of cinnamoyl isocyanate, which was prepared from cinnamoyl azide by Curtius rearrangement, with various aromatic amines, 2-amino-5-aryl-1,3,4-thiadiazoles and 2-amino-5-aryloxymethylene-1,3,4-thiadiazoles undermicrowaveirradiation. Compared to conventional methods, this synthesis has the advantages of mild reaction conditions
A Neat and Rapid Synthesis of 2‐Aryloxymethylene‐6‐Arylimidazo[2,1‐b]‐1,3,4‐Thiadiazole Under Microwave Irradiation
作者:Xicun Wang、Mangang Wang、Zhengjun Quan、Zheng Li
DOI:10.1080/00397910500297289
日期:2005.11
Abstract A neat and rapid procedure is reported for the synthesis of a variety of 2‐aryloxymethylene‐6‐arylimidazo[2,1‐b]‐1,3,4‐thiadiazole (3a–3r) by condensation reaction of 2‐amino‐5‐aryloxymethylene‐1,3,4‐thiadiazole (1a–1f) with ω‐bromoacetophenone (2a–2c) in ethanol solvent under microwave irradiation, which yielded a series of novel compounds. The yields are good to excellent. The procedure
A NEW ROUTE TO 2-(5-ARYL-2-FUROYLAMIDO)-5-ARYLOXYMETHYL-1,3,4-THIADIAZOLES
作者:Xicun Wang、Zheng Li、Yuxia Da
DOI:10.1081/scc-120003160
日期:2002.1
ABSTRACT The 2-(5-aryl-2-furoylamido)-5-aryloxymethyl-1,3,4-thiadiazoles 4 1–18 are synthesized by the reaction of 5-aryl-2-furoic acids 1 with phenylsulfonyl chloride and 2-amino-5-aryloxymethyl-1,3,4-thiadiazoles 3 under phase transfer catalysis.
2-benzofuryl substituted unsymmetrical ureas were synthesized by reactions of benzofuroyl isocyanate, which was prepared from benzofuroyl azide by Curtiusrearrangement, with various aromatic amines, 2-amino-5-(benzo-2-furyl)-1,3,4-thiadiazole, and 2-amino-5-aryloxymethylene-1,3, 4-thiadiazoles under microwave irradiation. Compared to conventional methods, this synthesis has the advantages of mild reaction
由苯并呋喃酰叠氮化物经库尔提斯重排制备的苯并呋喃酰异氰酸酯与各种芳香胺、2-氨基-5-(苯并-2-呋喃基)-1,3反应合成了一系列2-苯并呋喃基取代的不对称脲, 4-噻二唑和 2-氨基-5-芳氧基亚甲基-1,3, 4-噻二唑在微波辐射下。与常规方法相比,该合成方法具有反应条件温和、易于操作、收率高等优点。产品已通过分析和光谱(IR 和 1 H NMR)数据表征。