1988-22-3

Upstream product

• 2565-30-2 formyl chloride 
• 106-48-9 4-chloro-phenol 
• 556-63-8 lithium formate 
• 108-90-7 chlorobenzene 
• 64-18-6 formic acid 
• 109-94-4 formic acid ethyl ester 
• 79-37-8 oxalyl dichloride 
• 2258-42-6 formyl acetic anhydride 
• 104-88-1 4-chlorobenzaldehyde 
• 107-13-1 acrylonitrile 
• 920-66-1 1,1,1,3',3',3'-hexafluoro-propanol 
• 26944-31-0 N,N-Diformylacetamide 
• 67-66-3 chloroform 
• 24573-38-4 4-chlorophenolate 

Downstream Products

• 2005-08-5 4-chlorophenyl benzoate 
• 81932-03-8 4-chloro-α,α-difluoroanisole 
• 31354-51-5 N,N'-benzene-1,2-diyldiformamide 
• 6262-22-2 N-(4-formylaminophenyl)formamide 
• 7418-32-8 N-(2-nitrophenyl)formamide 
• 102-38-5 N-(3-nitrophenyl)formamide 
• 16135-31-2 p-nitroformanilide 
• 3342-77-6 N-formylanthranilic acid 
• 607-00-1 diphenylformamide 
• 6343-54-0 N-benzylformamide 
• 4252-31-7 N-formylbenzamide 
• 201230-82-2 carbon monoxide 
• 106-48-9 4-chloro-phenol 
• 1693-39-6 N-(4-hydroxyphenyl)formamide 

Relevant academic research and scientific papers

Acceleration of the Dakin reaction by trifluoroacetic acid

An acceleration of the Dakin reaction caused by addition of trifluoroacetic acid is described. The modified protocol converts aromatic aldehydes to the corresponding phenols within 4 hours at room temperature by means of hydrogen peroxide in acidic medium. This acceleration is attributed to the stability of hydrogen peroxide in an acidic medium. This modified protocol provides alternative and easy access to important phenolic precursors that have been used in the synthesis of various natural products.

The formyloxyl radical: Electrophilicity, C-H bond activation and anti-Markovnikov selectivity in the oxidation of aliphatic alkenes

In the past the formyloxyl radical, HC(O)O, had only been rarely experimentally observed, and those studies were theoretical-spectroscopic in the context of electronic structure. The absence of a convenient method for the preparation of the formyloxyl radical has precluded investigations into its reactivity towards organic substrates. Very recently, we discovered that HC(O)O is formed in the anodic electrochemical oxidation of formic acid/lithium formate. Using a [CoIIIW12O40]5- polyanion catalyst, this led to the formation of phenyl formate from benzene. Here, we present our studies into the reactivity of electrochemically in situ generated HC(O)O with organic substrates. Reactions with benzene and a selection of substituted derivatives showed that HC(O)O is mildly electrophilic according to both experimentally and computationally derived Hammett linear free energy relationships. The reactions of HC(O)O with terminal alkenes significantly favor anti-Markovnikov oxidations yielding the corresponding aldehyde as the major product as well as further oxidation products. Analysis of plausible reaction pathways using 1-hexene as a representative substrate favored the likelihood of hydrogen abstraction from the allylic C-H bond forming a hexallyl radical followed by strongly preferred further attack of a second HC(O)O radical at the C1 position. Further oxidation products are surmised to be mostly a result of two consecutive addition reactions of HC(O)O to the CC double bond. An outer-sphere electron transfer between the formyloxyl radical donor and the [CoIIIW12O40]5- polyanion acceptor forming a donor-acceptor [D+-A-] complex is proposed to induce the observed anti-Markovnikov selectivity. Finally, the overall reactivity of HC(O)O towards hydrogen abstraction was evaluated using additional substrates. Alkanes were only slightly reactive, while the reactions of alkylarenes showed that aromatic substitution on the ring competes with C-H bond activation at the benzylic position. C-H bonds with bond dissociation energies (BDE) ≤ 85 kcal mol-1 are easily attacked by HC(O)O and reactivity appears to be significant for C-H bonds with a BDE of up to 90 kcal mol-1. In summary, this research identifies the reactivity of HC(O)O towards radical electrophilic substitution of arenes, anti-Markovnikov type oxidation of terminal alkenes, and indirectly defines the activity of HC(O)O towards C-H bond activation.

Direct formylation of fluorine-containing aromatics with dichloromethyl alkyl ethers

Formylations of fluorine-containing aromatic compounds with dichloromethyl alkyl ethers have been investigated. Dichloromethyl propyl ether and dichloromethyl butyl ether have been applied for the formylation of fluorine-containing anisoles to give the corresponding aldehydes in good yields. Application of these ethers is preferable to that of methyl ether, which is prepared from volatile methyl formate. Reaction of fluorine-containing phenols with these dichloromethyl alkyl ethers did not give salicylaldehyde derivatives, leading instead to corresponding aryl formates in high yields. A plausible mechanism is discussed.

Electrochemical Hydroxylation of Arenes Catalyzed by a Keggin Polyoxometalate with a Cobalt(IV) Heteroatom

The sustainable, selective direct hydroxylation of arenes, such as benzene to phenol, is an important research challenge. An electrocatalytic transformation using formic acid to oxidize benzene and its halogenated derivatives to selectively yield aryl formates, which are easily hydrolyzed by water to yield the corresponding phenols, is presented. The formylation reaction occurs on a Pt anode in the presence of [CoIIIW12O40]5? as a catalyst and lithium formate as an electrolyte via formation of a formyloxyl radical as the reactive species, which was trapped by a BMPO spin trap and identified by EPR. Hydrogen was formed at the Pt cathode. The sum transformation is ArH+H2O→ArOH+H2. Non-optimized reaction conditions showed a Faradaic efficiency of 75 % and selective formation of the mono-oxidized product in a 35 % yield. Decomposition of formic acid into CO2 and H2 is a side-reaction.

Application of polydopamine sulfamic acid-functionalized magnetic Fe3O4 nanoparticles (Fe3O4@PDA-SO3H) as a heterogeneous and recyclable nanocatalyst for the formylation of alcohols and amines under solvent-free conditions

Herein, formylation of structurally different amines and alcohols with ethyl formate was carried out in the presence of a catalytic proportion of sulfonic acid supported on polydopamine (PDA)-encapsulated Fe3O4 nanoparticles as a heterogeneous, recyclable, and greatly efficient catalyst; this method provided the corresponding N-formyl compounds in good to excellent yields under solvent-free conditions. The magnetically catalytic system was recovered, by-passing the time-consuming filtration operation using an external magnet device. This procedure also increases the purity of the product and promises economic and ecological advantages. Furthermore, the recovery and reuse of the catalyst was demonstrated five times without detectable loss in the activity.

Solvent- and catalyst-free N-formylations of amines at ambient condition: Exploring the usability of aromatic formates as N-formylating agents

A solvent- and catalyst-free N-formylation protocol has been developed for amines (1s–21s) where aromatic formates (1r–6r) were used as the N-formylating agents. The amine substrates include both primary and secondary aromatic amines (1s–19s) as well as aliphatic amine (20s) and a primary amide (21s). Structures of both the aromatic formate and amine components strongly influenced the rate of the reaction and yield of the N-formamide products. The reaction condition is mild and easy to operate. This protocol can be done smoothly under ambient conditions and gives high yield of formamide products. Furthermore, the present method cannot be applied for the formylation of thiol group (22s). This signifies its possible use for the chemoselective N-formylation of amine in the presence of thiol functionality.

Three step procedure for the preparation of aromatic and aliphatic difluoromethyl ethers from phenols and alcohols using a chlorine/fluorine exchange methodology

Difluoromethyl ethers are prepared from phenols in three steps via their respective formate ester derivatives. The formates are first converted to dichloromethyl ethers by treatment with PCl5. These ethers are then induced to undergo chlorine/fluorine exchange to form the respective difluoromethyl ethers. The chlorine/fluorine exchange is carried out by either a room temperature, solvolytic process using THF-5HF or Et3N-3HF as exchange medium, where HF is the ultimate source of fluorine, or by a direct displacement process in sulfolane at 125 C, where KF is the source of fluorine. By one or another of these processes, virtually all phenols, electron-rich and electron-poor, can be converted to their respective difluoromethyl ethers in good yields. Aliphatic alcohols are also able to be converted to their difluoromethyl ether derivatives using the Et3N-3HF exchange medium.

O-acylation of substituted phenols with various alkanoyl chlorides under phase-transfer catalyst conditions

Esterification of several types of mono-and disubstituted phenols with various mono-and dialkanoyl chlorides was performed in phase-transfer catalysis conditions, using tetrabutylammonium chloride in a mixture of aqueous NaOH and dichloromethane. The process is particularly efficient (almost quantitative yields) as well as rapid (only 5 min reaction time, at a temperature of0°C). Taylor & Francis Group, LLC.

Oxidation of primary aliphatic and aromatic aldehydes with difluoro(aryl)-λ3-bromane

Oxidation of primary aliphatic aldehydes with p- trifluoromethylphenyl(difluoro)-λ3-bromane in dichloromethane at 0 °C afforded acid fluorides selectively in good yields, while that of aromatic aldehydes in chloroform at room temperature produced aryl difluoromethyl ethers. A larger migratory aptitude of aryl groups compared to primary alkyl groups during a 1,2-shift from carbon to an electron-deficient oxygen atom in bromane(III) Criegee-type intermediates will result in these differences in the reaction courses.

Hypervalent λ3-bromane strategy for Baeyer-Villiger oxidation: Selective transformation of primary aliphatic and aromatic aldehydes to formates, which is missing in the classical Baeyer-Villiger oxidation

A conceptually distinct, modern strategy for Baeyer-Villiger oxidation (BVO) was developed. Our novel method involves initial hydration of water to carbonyl compounds, followed by ligand exchange of hypervalent aryl-λ3-bromane on bromane(III) with the resulting hydrate, yielding a new type of activated Criegee intermediate. The intermediate undergoes BV rearrangement and produces an ester via facile reductive elimination of an aryl-λ3-bromanyl group, because of the hypernucleofugality. The novel strategy makes it possible to induce selectively the BV rearrangement of straight chain primary aliphatic as well as aromatic aldehydes, which is missing in the classical BVO: for instance, octanal and benzaldehyde afforded rearranged formate esters with high selectivity (>95%) under our conditions, while the attempted classical BVO produced only carboxylic acids. This firmly establishes the powerful nature of new methodology for BVO.