Base-mediated 1,3-dipolar cycloaddition of pyridinium bromides with bromoallyl sulfones: a facile access to indolizine scaffolds
作者:Chetna Jadala、Velma Ganga Reddy、Namballa Hari Krishna、Nagula Shankaraiah、Ahmed Kamal
DOI:10.1039/d0ob01696a
日期:——
synthetic strategy has been developed for the construction of substituted indolizines from a unique combination of pyridiniumsalts and 2-bromoallyl sulfones. This approach does not compromise with the diverse substitutions on both the pyridiniumsalts and 2-bromoallyl sulfones. Wide substrate scope, operational simplicity, milder reaction conditions and good to moderate yields are the merits associated with
A metal-free approach for the synthesis of amides/esters with pyridinium salts of phenacyl bromides via oxidative C–C bond cleavage
作者:Kesari Lakshmi Manasa、Yellaiah Tangella、Namballa Hari Krishna、Mallika Alvala
DOI:10.3762/bjoc.15.182
日期:——
O-benzoylation of various amines/benzyl alcohols with pyridinium salts of phenacyl bromides is demonstrated to generate the corresponding amides and esters. This protocol facilitates the oxidative cleavage of a C–C bond followed by formation of a new C–N/C–O bond in the presence of K2CO3. Various pyridinium salts of phenacyl bromides can be readily transformed into a variety of amides and esters which is an
用苯甲酰溴的吡啶鎓盐对各种胺/苄醇进行N-和O-苯甲酰化的有效,简单和无金属的合成方法被证明可以生成相应的酰胺和酯。该方案有助于在存在K 2 CO 3的情况下促进C–C键的氧化裂解,然后形成新的C–N / C–O键。苯甲酰溴的各种吡啶鎓盐可以很容易地转化为各种酰胺和酯,这是有机合成中常规酰胺化和酯化的另一种方法。高官能团耐受性,广泛的底物范围和操作简便性是当前方案的突出优点。
Ultrasound-promoted regioselective synthesis of chalcogeno-indolizines by a stepwise 1,3-dipolar cycloaddition
作者:Marcelo M. Vieira、Bianca T. Dalberto、Felipe L. Coelho、Paulo H. Schneider
DOI:10.1016/j.ultsonch.2020.105228
日期:2020.11
moderate to excellent yields from pyridinium salts and chalcogeno-alkynes. The reaction can be carried out under thermal conditions or by sonochemical processes in short reaction times. The stepwisecycloaddition reaction forming chalcogeno-indolizines is regioselective and extends to a broad range of functional groups. Furthermore, novel chalcogeno-alkynes are reported and the first derivatives of
Transition-Metal-Free Synthesis of Indolizines from Electron-Deficient Alkenes via One-Pot Reaction Using TEMPO as an Oxidant
作者:Yu Zhang、Huayou Hu、Fei Shi、Zhaole Lu、Xiaolei Zhu、Weiqiu Kan、Xiang Wang
DOI:10.1055/s-0035-1560973
日期:——
Abstract A one-pot method for the synthesis of multisubstituted indolizines from α-halo carbonyl compounds, pyridines, and electron-deficient alkenes is reported. The oxidative dehydrogenation reaction takes place under transition-metal-free conditions using TEMPO as an oxidant. This protocol uses ready available starting materials in a convenientprocedure under mild reaction conditions. A one-pot method
Facile one-pot tandem synthesis of perfluoroalkylated indolizines under metal-free mild conditions
作者:Dong He、Yuhong Xu、Jing Han、Hongmei Deng、Min Shao、Jie Chen、Hui Zhang、Weiguo Cao
DOI:10.1016/j.tet.2017.01.005
日期:2017.2
A direct metal-free method for the synthesis of perfluoroalkylated indolizines by means of DIPEA-promoted tandem CN/CC bond formation was developed. Various substituted pyridines and bromoacetyl derivatives with methyl perfluoroalk-2-ynoates proceeded smoothly in this mild transformation, and the desired products were obtained in good to excellent yields under air.
开发了一种直接无金属的方法,该方法通过DIPEA促进的串联C N / C C键的形成来合成全氟烷基化的吲哚嗪。在这种温和的转化过程中,各种被全氟烷基-2-丙酮酸甲酯取代的吡啶和溴代乙酰基衍生物可顺利进行,并在空气中以良好或优异的收率获得所需的产物。