A Deoximation Method for Deprotection of Ketones and Aldhydes Using a Graphene‐Oxide‐Based Co‐catalysts System

Abstract

The deoximation of a wide range of ketoximes and aldoximes to their corresponding carbonyl compounds with high yields has been achieved using graphene oxide (GO) and sodium nitrite (NaNO2) as highly efficient catalysts and air as the green oxidant under mild conditions. The mechanism of deprotection and recycling use of catalyst were revealed in deep experiment. The carboxylic acid groups on the GO were essential for high catalytic activity.

AIBN‐Initiated Oxidative Deoximation Reaction: A Metal‐Free and Environmentally‐Friendly Protocol

“…A series of conventional solvents such as EtOAc, EtOH, MeCN, 1,4-dioxane, tetrahydrofuran (THF) and toluene were tested (Table 1, entries 3-8). The reaction in MeCN afforded the highest product yield at 83% (Table 1, entries 5 vs. [2][3][4][6][7][8]. However, considering the environment-protection issues, DMC was the favourable reaction solvent, despite the resulted slight decrease of the product yield in comparison of that of the reaction in MeCN (Table 1, entries 2 vs. 5).…”

“…For example, the strategy has been applied in the total synthesis of erythronolide A [2] . It is also used for product purification in the industrial production of watermelon ketone because the watermelon ketoxime is easy to crystallize [3] . Moreover, since some oximes can be prepared from non‐carbonyl starting materials, deoximation reaction is the key process for the synthesis of the related ketones, and the production of carvone from limonene is a typical example [4] .…”

“…[2] It is also used for product purification in the industrial production of watermelon ketone because the watermelon ketoxime is easy to crystallize. [3] Moreover, since some oximes can be prepared from non-carbonyl starting materials, deoximation reaction is the key process for the synthesis of the related ketones, and the production of carvone from limonene is a typical example. [4] Deoximation reaction may occur under acidic conditions, but the process usually require stoichiometric/excess additives leading to solid waste generation, [5] or the high-loading and irritant reagents such as Si 2 Cl 6 , [6] SnCl 2 /TiCl 3 [7] and p-toluenesulfonic acid.…”

Eco-friendly methoximation of aromatic aldehydes and ketones using MnCl 2 .4H 2 O as an easily accessible and efficient catalyst

“…However, once dehydration took place and compound ( B ) was formed, it is less likely that the latter could be hydrolyzed to the starting material ( A ). The validity of this conjecture stems from the fact that oxime ethers are relatively stable to hydrolysis [ 68 , 69 ] and that the salt is unable to catalyse deoximation [ 70 ] under the reaction conditions.…”

Sustainable and Efficient Route for the Regeneration of Carbonyl Compounds from Oximes Using Aqueous Extract of Sapindus laurifolia under Microwave Radiation

“…Some of the well-known deoximating agents are N 2 O 4 , pyridinium chlorochromate (PCC), tert -butyl hydroperoxide (TBHP), KMnO 4 /alumina, (PhSeO) 2 O, TMSCl/NaNO 2 , Raney nickel, sodium perborate/HOAc, NaHSO 3 , etc., and several transition-metal salts involve Tl­(NO 3 ) 3 , Cr­(OAc) 2 , Mn­(OAc) 3 , trimethylsilyl chlorochromate, BiBr 3 /Bi­(OTf) 3 , 2-nitro-4,5-dichloropyridazin-3­(2 H )-one, and Al­(NO 3 ) 3 ·9H 2 O in the presence of catalytic amounts of NaBr in CH 2 Cl 2 at room temperature . Furthermore, tetraethyl ammonium chlorochromate (TEACC) in dimethylsulfoxide, potassium permanganate–graphite, citric acid, and many other reagents − have recently been reported as deoximating agents. However, most of these reagents are toxic, corrosive, and expensive and take a longer reaction time for completion.…”