39518-07-5Relevant academic research and scientific papers
Blue LED-Mediated N-H Insertion of Indoles into Aryldiazoesters at Room Temperature in Batch and Flow: Reaction Kinetics, Density Functional Theory, and Mechanistic Study
Maiti, Debajit,Das, Ranajit,Sen, Subhabrata
, p. 2522 - 2533 (2021)
Mild blue light-mediated N-H insertion of indole and its derivatives into aryldiazoesters has been reported in a batch and flow strategy to afford the corresponding N-alkylated product in moderate-to-excellent yield. Detailed high-performance liquid chromatography-based reaction kinetics measurements, control experiments, and kinetic isotope effect reveal that 3-substituted indoles with electron-withdrawing groups such as -CN and -CHO facilitated the product formation, whereas the electron-donating group retarded the process. The neutral indole performed in between them. Furthermore, Hammett plot and density functional theory-based transition-state optimization studies showed substantial correlation of the electronic nature of the substituents at the C3 position of indoles with the rate of the N-H insertion reaction. The strategy was utilized to synthesize a key intermediate for the natural product (-)-psychotrimine.
Photolytic amino etherification reactions of aryl diazoacetates with N-heterocycles and a stoichiometric amount of dioxane/tetrahydropyran in aqueous medium: Synthesis of 1,4-dioxepane/1,4,7-dioxazonan-6-one systems
Das, Ranajit,Maiti, Debajit,Sen, Subhabrata
supporting information, p. 8533 - 8544 (2021/11/17)
Herein we have reported a blue LED mediated reaction of aryl diazoacetate with a stoichiometric amount of 1,4-dioxane/tetrahydropyran (THP) and various heterocycles like indoles, pyrroles, phthalimides, thiazolidinediones and hydantoins in water. During the reaction, various aryl diazoacetates were converted to oxonium ylides by reacting with 1,4-dioxane and THP. These ylides generated in aqueous medium (under metal- and base-free conditions) were then used for the amino etherification of the aforementioned heterocycles in excellent yield. The ylides underwent a [1,2] shift to afford substituted 1,4-dioxepanes. Phthalimide products were also converted to 1,4,7-dioxazonan-6-ones. Reaction kinetics, Hammett's plot and DFT calculations (solvent phase) rationalize the ylide formation and subsequent reactions with the nucleophiles. The reaction was also demonstrated at the multigram scale. This amino etherification reaction of aryl diazoacetates in aqueous medium demonstrated a sustainable process of converting toxic 1,4-dioxane in functionalizing heterocycles. This journal is
