KOH介导的分子内酰胺化和亚磺酰化:访问3-(芳硫基)咪唑并[1,2- a ]吡啶-2-醇的直接方法
摘要:
通过KOH介导的2-氨基吡啶溴化物与芳基硫醇的反应,已经开发出一种简单且简便的合成3-(芳硫基)咪唑并[1,2 - a ]吡啶-2-醇的方法。该方法以中等至优异的产率(56–95%)提供了范围广泛的3-(芳硫基)咪唑并[1,2 - a ]吡啶-2-醇,并具有出色的官能团耐受性。该协议的合成效用通过革兰氏规模的反应和制备的2-芳基-3-(证明p -tolylthio)咪唑并[1,2一]从3-(吡啶p -tolylthio)咪唑并[1,2一]吡啶-2-醇。
通过使用Pd(TFA)使2-氨基-1-(2-乙氧基-2-氧乙基)吡啶鎓盐与2-溴芳基醛反应,可直接合成一氧化铬修饰的咪唑并[1,2- a ]吡啶)2作为催化剂,Cu(OAc)2作为氧化剂。总体策略涉及串联碱基介导的酰胺化和Knoevenagel缩合,然后进行钯催化的Wacker型氧化和分子内C–O偶联反应。该方法简单,耐受不同的官能团,并给出中等程度到良好的产色量[2',3':4,5]咪唑并[1,2 - a ]吡啶-12-衍生物。发达的串联反应也成功地用于合成吡喃并稠合的咪唑并[1,2- a]。通过使用3-溴-3-芳基丙烯醛制备]吡啶。
Novel, heterocyclic derivatives of trithiophosphoric acid have been achieved through phosphorylation of quaternary salts of N-heterocycles with phosphorus trichloride, the iminohalophosphines, thus obtained in situ were subjected to nucleophilicsubstitution with mercaptans in organic solvents in the presence of HCl acceptors, preferably triethylamine. Synthesized derivatives exhibited potential insecticidal
A Facile Synthesis of 3‐(Arylthio)imidazo[1,2‐
<i>a</i>
]pyridin‐2(3H)‐ones from 2‐Aminopyridinium Bromides and Sodium Arenesulfinates
作者:Saroj、Krishnan Rangan、Anil Kumar
DOI:10.1002/ejoc.202000996
日期:2020.12.7
Synthesis of 3‐(arylthio)imidazo[1,2‐a]pyridin‐2(3H)‐ols has been achieved through a catalyst‐free, one‐potreaction of 2‐aminopyridinium bromides with sodium arenesulfinates. The tandem reaction involved intramolecular amidation followed by sulfenylation and afforded a wide range of 3‐(arylthio)imidazo[1,2‐a]pyridin‐2(3H)‐ols in moderate to excellent (33–85 %) yields. The method exhibited broad substrate
通过无催化剂的2-氨基吡啶溴化物与芳烃亚磺酸钠的一锅反应,可以合成3-(芳硫基)咪唑并[1,2 - a ]吡啶-2(3H)-醇。串联反应涉及分子内酰胺化,然后进行亚磺酰化,并以中等至极好(33-85%)的产率提供了多种3-(芳硫基)咪唑并[1,2 - a ]吡啶-2(3H)-醇。该方法具有广泛的底物范围,具有宽泛的官能团耐受性,适用于克级合成。
An efficient access to 2,3-diarylimidazo[1,2-a]pyridines via imidazo[1,2-a]pyridin-2-yl triflate through a Suzuki cross-coupling reaction-direct arylation sequence
An efficient method to prepare 2,3-diarylimidazo[1,2-a]pyridines is described. The procedure involves a Suzuki cross-coupling reaction followed by a directarylation at position 3. Imidazo[1,2-a]pyridin-2-yl triflate was identified as a suitable coupling partner, permitting access to a variety of highly functionalized 2,3-diarylimidazo[1,2-a]pyridines.
描述了一种制备2,3-二芳基咪唑并[1,2- a ]吡啶的有效方法。该过程涉及Suzuki交叉偶联反应,然后在3位直接芳基化。咪唑并[1,2- a ]吡啶-2-基三氟甲磺酸酯被确定为合适的偶联伴侣,从而可以使用各种高度官能化的2, 3-二芳基咪唑并[1,2- a ]吡啶。
Metal-free synthesis of pyridin-2-yl ureas from 2-aminopyridinium salts
作者:Saroj、Om P.S. Patel、Krishnan Rangan、Anil Kumar
DOI:10.1016/j.tetlet.2019.07.030
日期:2019.8
domino approach has been developed for the synthesis of pyridin-2-yl urea derivatives via the reaction of 2-aminopyridinium salts and arylamines. The developed strategy tolerated a wide range of functional groups and afforded pyridin-2-yl ureas in moderate to good yields. The reaction was postulated to involve tandem cyclization, intermolecular nucleophilic addition, ring opening, and demethylation.
Synthesis of Functionalized Chiral Phosphines and Chlorothiophosphonates
作者:Vijaya Kabra、Priti Kaushik、Suneeta Ojha
DOI:10.1080/10426500601096609
日期:2007.3.15
asymmetric phosphorusatom, induced diastereotopicity in the geminal N-methylene group. Halophosphines have been synthesized as a key precursor, which, in situ converted to stable tetracoordinated phosphorus by oxidation with elemental sulfur to obtain a new series of synthon compounds with an active chlorineatom. Chlorothiophosphonates have also exhibited a similar chemical-shift nonequivalence of geminal