Carbonylation dimethyl formamide

BROME (French) (7726-95-6) A powerful oxidizer. Violent reaction with reducing agents. Can cause fire and explosions in contact with organic or other readily oxidizable materials. Contact with water or steam forms hydrobromic acid and oxygen. Contact with aqueous ammonia, acetaldehyde, acetylene, acrylonitrile, hydrogen may cause violent reactions. Anhydrous material reacts violently with aluminum, titanium, mercury, or potassium wet material reacts with other metals. Incompatible with many materials, including alcohols, antimony, alkali hydroxides, arsenites, azides, boron, calcium nitrite, cesium monoxide, carbonyls, dimethyl formamide, ethyl phosphine, fluorine, ferrous and mercurous salts, metals. 

Carbonyl insertion into 5-substituted 2-(o-bromo-/>-isopropylphenyl-amino)pyridines (275) in the presence of bis(triphenylphosphine)palla-dium(II) chloride, triphenylphosphine, and tributylamine under 200 psi-pressure of carbon monoxide at 100°C in aqueous ferr-butanol or dimethyl-formamide gave 8-substituted 2-isopropyl-l 17/-pyrido[2,l-b]quinazolin-l 1 -ones (276) (87JOC2469). 

In 2,4-difluorobenzaldehyde and 2,4-difluorophenyl ketones, not only the 4-F but also the 2-F will be replaced by the benzylsulfanyl group, provided the reaction is carried out in dimethyl-formamide using an appropriate amount of phenylmethanethiol.64 However, with tetrahy drofuran as the solvent, the 2-F is predominantly substituted to give 5, independent of the nature of the substituent at the carbonyl group. This selectivity is explained by assuming a chelation-controlled addition as the primary step.64... 

The oxyphosphoranes are made from the reaction of a trivalent phosphorus compound with a carbonyl compound. 6 DMF=dimethyl-formamide HFIP=hexafluoroisopropyl alcohol. c l-Phospha-2,8,9-trioxaadamantane. d ca. 0-2m soln. ca. 1m soln. tea. 2m soln. 

Valuable orgartic solvents, such as formamides, arc available from HCN aird these syntheses could be interesting substitute methods for ammonia or amine carbonylation reactions. Formamide is formed during the hydrolysis of HCN under dilute, slightly basic conditions (pH 7-10). with polymers being formed in concentrated solutions (Section 3.4). Dimethyl formamide can be obtained from HCN and CH3OH in the presence of T1CI4 or TeCU as catalysts 43]. 

Reaction with ketones and amides. In the presence of a trace of N,N-dimethyl-formamide or of pyridine, the reagent adds to the carbonyl group of cyclohexanone... 

Reductive carbonylation of 1,1-dibromocyclopropanes with tetracarbonylnickel in dimethyl-formamide in the presence of a nucleophile is a powerful method for direct introduction of carboxylic acid functions to cyclopropanes. Nucleophiles, such as alcohols, amines, and silylamines, are particularly reactive and give cyclopropyl esters and amides, respectively, in reasonable to good yields, e.g. formation of 5 and... 

Concerning the influence of the solvent, while the reaction afforded low conversions in protic solvents, high conversions were obtained in dimethyl-formamide or dichloromethane. Under these conditions the catalyst was truly heterogeneous, but its activity decreased gradually upon successive reuses (from 75% to 51% yield of product 110). The main cause of deactivation could be the covalent attachment of methyl vinyl ketone to the pyridine nitrogen of the polymer IR spectra of the catalyst before and after extensive deactivation showed that reuse of the catalyst caused the appearance of bands from 1750 to 1650 cm" , which are attributable to the presence of several types of carbonyl... 

Finally, mention should be made of the formylation of ylides by dimethyl-formamide and carbonyl chloride, which is analogous to the Vilsmeier reaction.456,464... 

Scheme 24), trimethylsilyl chloride (Scheme 33), epoxides(Scheme 33), and with various carbonyl compounds such as aldehydes and ketones including a,p-unsaturated or a-selenylated ones as well as with dimethyl formamide a-Silylcyclopropyllithiums, which are less nucleophilic, do not react... 

Polyester fibers are composed of linear chains of polyethylene terephthalate (PET), which produces benzene, benzoic acid, biphenyl, and vinyl terephthalate on pyrolysis. Acrylic fibers comprise chains made up of acrylonitrile units, usually copolymerized with less than 15% by weight of other monomers, e.g., methyl acrylate, methyl methacrylate, or vinylpyrrolidone. Thermolysis results in the formation of acrylonitrile monomer, dimers, and trimers with a small amount of the copolymer or its pyrolysis product. In this case, the acrylic is Orion 28, which contains methyl vinyl pyridine as comonomer. Residual dimethyl formamide solvent from the manufacturing process is also found in the pyrolysis products. Cotton, which is almost pure cellulose, comprises chains of glucose units. The pyrolysis products of cellulose, identified by GC/MS, include carbonyl compounds, acids, methyl esters, furans, pyrans, anhydrosugars, and hydrocarbons. The major pyrolysis products are levoglucosan (1,6-anhydro-B-D-glucopyranose) and substituted furans. 

Sodium trihydridocyanoborate in hexamethylphosphoramide provides a convenient and selective system for the reductive removal of iodo, bromo, tosyloxy, and, indirectly, hydroxy groups carbonyl oxygen can be removed in the presence of tosylhydrazine in dimethyl-formamide-sulfolane at 100-105° . Thiourea dioxide in alkaline solution has been recommended as a convenient and economical reagent for the reduction of ketones to sec. alcohols . 

A-Iodosuccinimide reacts with a-hydroxy-carboxylic acids in an oxidative decarboxylation sequence to give carbonyl compounds. A dehydrative decarboxylation of 2,3-disubstituted 3-hydroxycarboxylic acids, using dimethyl-formamide acetals, has been reported. Photosensitized oxygenation of diethyl... 

Hence, complex (16) reacts with CO in noncoordinating solvents, such as dimethyl-formamide (DMF) or acetone but not in acetonitrile to afford the carbonyl complex (18). The spectroscopic data support a rapid reversible binding of CO from (17) to (18) (Scheme 2.11). 

Recently, the synthetic utility of dimethyl formamide (DMF) as the nucleophilic trigger in aryne MCRs was developed independently by the Miyabe and Yoshida groups. The three-component coupling reaction between aryne, DMF, and an active methylene compound such as acetyl acetone, dibenzoyl methane, cyclohexane 1,3-dione, etc. resulted in the formation of either 2H-chromenes 105 or coumarin derivatives 106 [75,76]. The insertion of fhe carbonyl group of DMF to the aryne generates the o-quinone methide intermediate 104. Subsequent reaction of 104 with cyclic or acyclic 1,3-diketones as the third component resulted in the formation of 2H-chromenes 105. Intriguingly, furnished coumarin derivatives 106 were formed when 3-ketoester or a-(hetero)aryl esters were used as the third component (Scheme 53). 

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