Proton-Mediated Practical Synthesis of McGeachin-Type Bisaminals
作者:Hongguang Du、Jiaxi Xu、Zhanhui Yang、Yang Chen、Tingting Wang
DOI:10.1055/a-1490-1241
日期:2021.8
proton-mediated practicalsynthesis of McGeachin-type bisaminals from 2-(alkylamino)arenecarbaldehydes and primary amines is achieved, with trifluoroacetic acid as the proton donor. The use of a proton, a smallest electrophilic activator, allows previously inviable ortho-substituted anilines and linear and branched aliphatic amines to be viable substrates for McGeachin bisaminal synthesis. Overcoming
isolated from traditional African herbal medicine Cryptolepis sanguinolenta, and its broad spectrum of biological activities has been illuminated in past decades. In this study, neocryptolepine and its derivatives (1-49) were designed and synthesized from economical and readily available starting materials. Their structures were confirmed by protonnuclearmagneticresonance, carbon nuclearmagnetic resonance
The synthesis of novel pyrrolidine or pyrrolizine‐fused benzosultams is described. A number of (E)‐N‐(2‐formylphenyl)‐N‐alkyl‐2‐phenylethenesulfonamides derivatives were synthesized and subjected to intramolecular [3 + 2] cycloaddition with azomethine ylides derived in situ from the reaction with sarcosine, phenylglycine, and L‐proline.
An efficient catalyst-free and diastereoselective synthesis of novel dihydropyrano[2,3-d]pyrimidine and dihydropyrano[3,2-c]chromen-annulated benzosultams is described. A number of (E)-N-(2-formylphenyl)-N-methyl-2-phenylethenesulfonamides were synthesized and underwent a one-pot dominoKnoevenagelhetero-Diels–Alderreaction, respectively, with N,N-dimethylbarbituric acid and 4-hydroxycoumarin in
描述了新型的二氢吡喃并[2,3- d ]嘧啶和二氢吡喃并[3,2 - c ]色铬修饰的苯并阿舒他姆的无催化剂和非对映选择性合成。合成了许多(E)-N-(2-甲酰基苯基)-N-甲基-2-苯基乙磺酰胺,并分别与N,N-二甲基巴比妥酸和4进行了一锅多米诺Knoevenagel杂Diels-Alder反应。-羟基香豆素在水中,以中等至极好的收率得到所需的产物。
Efficient access to novel tetra- and pentacyclic dihydroquinolin-2-ones by catalyst-free domino Knöevenagel hetero-Diels–Alder reactions from N-(2-formylphenyl)-N-methylcinnamamides and cyclic 1,3-dicarbonyls in water
An efficientcatalyst-freesynthesis of novel annulated hybrid derivatives of two known scaffolds, dihydroquinolinone and pyranopyranone, pyranopyrimidinedione, pyranocoumarin or chromenone is described. N-(2-Formylphenyl)-N-methylcinnamamides underwent a one-pot domino Knöevenagel hetero-Diels–Alder reaction with dimedone, N,N-dimethylbarbituric acid, 1,3-indanedione, 4-hydroxycoumarins and 4-hyd