Synthesis of Acyl Hydrazides from Carboxamides and Hydrazine Hydrate Under Metal‐Free Conditions at Room Temperature

Abstract

Synthesis of acyl hydrazides from amides has been achieved at room temperature through N‐activation reactions. A wide spectrum of functionalized primary and secondary amides was initially converted into N‐Boc, N‐nitroso and N‐tosyl amides and subjected to transamidation with hydrazine hydrate to obtain the desired acyl hydrazides in 76–94% yields. Broad substrate scope, shorter reaction time and mild reaction conditions are the merits of the developed methodology.

Synthesis of Acyl Hydrazides and Hydrazones from Activated Amides

“…9 According to the general procedure, 1-(4-methylbenzoyl)pyrrolidin-2-one (203 mg, 1.0 mmol) gave 2d (122 mg, 0.81 mmol, 81% yield, light yellow solid) after column chromatography (CH 2 Cl 2 /MeOH, 19:1); mp 115-116 °C. 7 According to the general procedure, 1-(4-(tert-butyl)benzoyl)pyrrolidin-2-one (245 mg, 1.0 mmol) gave 2e (173 mg, 0.90 mmol, 90% yield, white solid) after column chromatography (CH 2 Cl 2 /MeOH, 19:1); mp 124-125 °C. 7 According to the general procedure, 1-(4-methoxybenzoyl)pyrrolidin-2-one (219 mg, 1.0 mmol) gave 2f (113 mg, 0.68 mmol, 68% yield, white solid) after column chromatography (CH 9 According to the general procedure, 1-(4-chlorobenzoyl)pyrrolidin-2one (223 mg, 1.0 mmol) gave 2i (154 mg, 0.90 mmol, 90% yield, white solid) after column chromatography (CH 2 Cl 2 /MeOH, 19:1); mp 163-166 °C.…”

“…6 Singh and Kandasamy have investigated the synthesis of acyl hydrazides from amides. 7 However, to date, there have been no documented instances of extensions into acyl hydrazones. To successfully synthesize acyl hydrazones from acylation reaction precursors through a one-pot reaction, certain conditions must be met by the acylation reaction precursors.…”

Transamidation of secondary carboxamides and amidation of esters are facilitated by magnetic Co@NC nanoparticles, as a highly efficient and recyclable catalyst under neat conditions

“…14–17 Initially, planar amides are transformed into twisted amides (such as N -Boc, N -Cbz, N -Ts, N -benzoyl cytosine) facilitated by metal catalysts (Co, Zn, Ni, Cu, Pd), additives or bases. 18–22 Recently, a novel approach has been reported for the direct amidation of esters using non-nucleophilic amines to synthesize amides employing various catalysts. 23,24 Consequently, numerous effective catalysts have been employed for transamidation across various amides.…”

Visible-Light-Induced Siloxycarbene Addition to N═N of Azodicarboxylates: Synthesis of Acyl Hydrazides from Acylsilanes

“…Prior syntheses of acyl hydrazides were accomplished from the alcohols, aldehydes, alkanes in the presence of carbon monoxide, ketoacids, carboxylic acids, and carboxamides . However, to the best of our knowledge, there is no report for the synthesis of acyl hydrazides from ketones or acylsilanes.…”