Efficient synthesis of nebularine and vidarabine via dehydrazination of (hetero)aromatics catalyzed by CuSO₄in water

Abstract

A simple dehydrazination reaction has been achieved in the presence of a catalytic amount of CuSO 4 for the first time. With CuSO 4(2 mol%) as a catalyst and water as a solvent, the dehydrazination products were obtained in good yields (66-95%). Moreover, the drugs nebularine and vidarabine were afforded successfully, and vidarabine could be produced on a 0.923 kg scale, which shows good potential for industrial applications.

Dehydrogenation of the NH−NH Bond Triggered by Potassium tert‐Butoxide in Liquid Ammonia

“…To the best of our knowledge, it is a novel and effective method to dehydrazinate phenylhydrazine. [14] The above results show an effective and unique strategy for dehydrogenating the NHÀNH bond to give the N=N bond. To further broaden its synthetic utility, we applied this tBuOK ( [a]…”

Dehydrogenation of the NH−NH Bond Triggered by Potassium tert‐Butoxide in Liquid Ammonia

“…To the best of our knowledge, it is a novel and effective method to dehydrazinate phenylhydrazine. [14] The above results show an effective and unique strategy for dehydrogenating the NHÀNH bond to give the N=N bond. To further broaden its synthetic utility, we applied this [a] Unless otherwise mentioned, all of the reactions were carried out using 1 a (0.5 mmol), additive, and solvent (6 mL) in a sealed tube with air.…”

Catalyst‐Free Difunctionalization of Activated Alkenes in Water: Efficient Synthesis of β‐Keto Sulfides and Sulfones

“…Then, diethyl 1-phenylvinyl phosphate (1a,0 .20 mmol) and H 2 O( 0.5 mL) were successively injected into the reaction tube with stirring. The reaction mixture was stirred vigorously at room temperature for 3h.T hereafter,t he mixture was extracted with ethyl acetate (4 ). The combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure.…”

“…In light of this, simpler andm ore sustainable strategies for alkene difunctionalizationa re also appealing and necessary.W ater,a na ttractive alternative of organic solvents, is environmentally friendly,nontoxic, and economic.A dditionally,o wing to its extraordinary properties, water can be used to tune the reaction selectivity in chemical synthesis. [3,4] Moreover,g iven the advantages of low cost and purification simplicity,s ynthetic procedures without any extra additivesh ave long been developedi nb othl aboratory synthesis and pharmaceutical industry. [5] Seeking as imple andh ighly efficient methodf or alkene difunctionalization in water under catalyst-free conditions is in accordance with the principles of green chemistry,w hich is also av aluable task.…”