Formamides ketones

Allylzinc bromide (Bromo-2-propenylzinc) [18925-10-5] CH2=CHCH2ZnBr Formamide, Ketones See Formamide Organozinc compounds See also GRIGNARD REAGENTS C3H5BrZn... 

The conversion of an aldehyde or ketone into the corresponding amine by heating with ammonium formate or with formamide and formic acid at about... 

Ai,A/-bis(hydroxymethyl) formamide [6921-98-8] (21), which in solution is in equiUbrium with the monomethylol derivative [13052-19-2] and formaldehyde. With ben2aldehyde in the presence of pyridine, formamide condenses to yield ben2yhdene bisformamide [14328-12-2]. Similar reactions occur with ketones, which, however, requite more drastic reaction conditions. Formamide is a valuable reagent in the synthesis of heterocycHc compounds. Synthetic routes to various types of compounds like imida2oles, oxa2oles, pyrimidines, tria2ines, xanthines, and even complex purine alkaloids, eg, theophylline [58-55-9] theobromine [83-67-0], and caffeine [58-08-2], have been devised (22). 

Preparation of Amines. Amines are prepared by heating aUphatic, aromatic, or cycHc ketones with ammonium formate, formamide, or an A/-substituted ammonium formate at 165—190°C (Leuckart reaction). For example, cx-methylbenzylamine is prepared by the reaction of acetophenone with ammonium formate. 

The physical properties of finish removers vary considerably due to the diverse uses and requirements of the removers. Finish removers can be grouped by the principal ingredient of the formula, method of appHcation, method of removal, chemical base, viscosity, or hazardous classification. Except for method of apphcation, a paint remover formulation usually has one aspect of each group, by which it can be used for one or more appHcations. A Hst of the most common organic solvents used in finish removers has been compiled (3). Many are mentioned throughout this article others include ethyl lactate [97-64-3] propylene carbonate [108-32-7] furfural alcohol [98-01-1/, dimethyl formamide [68-12-2] tetrahydrofuran [109-99-9] methyl amyl ketone [110-43-0] dipropylene glycol methyl ether [34590-94-8] and Exxate 600, a trade name of Exxon Chemicals. 

A condensible blowdown tank, designed on a similar basis to that described above for phenol, may be provided in other services where a conventional condensible blowdown drum would not be acceptable (e.g., due to effluent water pollution considerations). Examples of such cases are methyl ethyl ketone (MEK) and dimethyl formamide (DMF). A suitable absorbing material is specified (e.g., a lube oil stock for MEK water for DMF), and the design must include consideration of maximum permissible operating temperatures to prevent excessive vapor evolution or the boiling of water. 

Furfuryl dimethyl amine is first produced. This may conveniently be accomplished by employing the Leuckart synthesis known to those skilled in the art, which involves the use of an aldehyde or a ketone, and formate of ammonia or an amine, or corresponding formamide derived by dehydration of formate of ammonia or an amine. 

The reaction with disubstituted formamides and phosphorus oxychloride, called the Vilsmeier or the Vilsmeier-Haack reaction,is the most common method for the formylation of aromatic rings. However, it is applicable only to active substrates, such as amines and phenols. An intramolecular version is also known.Aromatic hydrocarbons and heterocycles can also be formylated, but only if they are much more active than benzene (e.g., azulenes, ferrocenes). Though A-phenyl-A-methyl-formamide is a common reagent, other arylalkyl amides and dialkyl amides are also used. Phosgene (COCI2) has been used in place of POCI3. The reaction has also been carried out with other amides to give ketones (actually an example of 11-14),... 

Disubstituted formamides can give addition of 2 mol of Grignard reagent. The products of this reaction (called Bouveault reaction) are an aldehyde and a tertiary amine.The use of an amide other than a formamide can give a ketone instead... 

Alkylation of enamines Addition of amines to triple-bond compounds Addition of amines to aldehydes or ketones Reaction between Grignard reagents and formamides Reaction of phosphonates with aldehydes or ketones... 

Whereas condensation of a-hydroxy ketones such as benzoin and acetoin on heating with formamide [240] or ureas in acetic acid [239, 242] to form imidazoles such as 769 or 770 is a well known reaction, only two publications have yet discussed the amination of silylated enediols, prepared by Riihlmann-acyloin condensation of diesters [241], by sodium, in toluene, in the presence of TCS 14 [241, 242]. Thus the silylated acyloins 771 and higher homologues, derived from Riihl-... 

Methyl ethyl ketone (MEK), see 2-Butanone N-methyl formamide 8-4... 

Mistryukov, E. A. et al., Mendeleev Comm., 1993, (6) 242 Adding formamide to a reaction mixture of allylzinc bromide and a ketone as a proton source for a Barbier reaction in ether or tetrahydrofuran gave uncontrollable explosion-like reaction. The reaction proceeded smoothly when starting from zinc dust and allyl bromide, with both formamide and the ketone in situ. 

Paper chromatography using Whatman No. 1 paper was once used to determine the homogeneity of halcinonide. 60 Twenty percent formamide in methanol comprises one stationary phase and methylisobutyl ketone-formamide (20 1) is the mobile phase. A second solvent system uses 25% propylene glycol-chloroform as the stationary phase and toluene saturated with propylene glycol as the mobile phase. 

To a cooled mixture of 34 g 30% H202 and 150 g formic acid, add dropwise a solution of 32.4 g (0.2M) isosafrole in 120 ml acetone (keep temperature below 40°). Let stand about twelve hours and evaporate in vacuum. Add 60 ml methanol and 360 g 15% sulfuric acid to the residue and heat on water bath three hours. Cool, extract with ether or benzene and evaporate in vacuum the extract to give 20 g 3,4-methlenedioxybenzyl-methyl ketone (I) (can distill 115/2). Add 23 g (I) to 65 g formamide and heat at 190° for five hours. Cool, add 100 ml H202, extract with benzene and evaporate in vacuum the extract. Add 8 ml methanol and 57 ml 15% HCI to residue, heat on water bath two hours and evaporate in vacuum (or basify with KOH and extract the oil with benzene and dry, evaporate in vacuum) to get about 11 g MDA. In this, as in the other syntheses, either the cis or trans (alpha or beta) propenylbenzenes (or a mixture) may be used. 

M p-methoxy (or other group)-Br-benzene (see this paper for prepartion) and 4.6 g Mg. Rapidly add 18.5 g chloroacetone in 50 ml ether. Evaporate the ether by heating in oil bath and then at about 135° for one hour. Cool and add ice and dilute HCI extract the oil with ether and dry, evaporate in vacuum to get about 11 g product (can distill 106/18). 0,057 M of the ketone product in 16 g formamide in 100 ml round bottom flask, with an air condenser. Heat twelve hours at boiling and then reflux with 35 ml 30% NaOH eleven hours and separate the amine layer and dry, evaporate in vacuum to get the amphetamine. 

Mix 0.25M substituted benzaldehyde, 0.3M nitroethane, 50 ml dry toluene and 5 ml n-butylamine (or other amine), and reflux 3 hours with a Dean-Stark trap (or prepare the nitro-propene as described elsewhere here). Add 50 g iron powder and 1 g FeCl3 optional) and reflux while adding 90 ml concentrated HCI over 3 hours. Reflux 1 hour more, add 2 liters of water and extract 3 times with ether, then dry and evaporate in vacuum (or steam distill until about 3.5 liters of distillate is obtained extract the distillate 3 times with toluene wash the toluene layers with 7 g NaHS03 in 225 ml of water, then 3 times with water and dry, evaporate in vacuum) to get the ketone. Mix 0.13M ketone, 28 g formamide (or dimethyl-formamide if the N.N-dimethylamine is desired) and 3 ml formic acid and heat at 160°. Add 3 more ml formic acid and heat 16 hours at 170-180° adding formic acid from time to time to keep the pH acid. Distill off the water formed (about 16 ml), cool and extract with 3X70 ml benzene. Distill off the benzene and reflux the residue 7 hours with 30 ml concentrated HCI. Chill, basify with 10% NaOH and extract with 3X70 ml ether. Dry and evaporate the ether in... 

Section 4.2.1 will be devoted to heterocycles, section 4.2.2 will cover other kinds of protomeric tautomeric equilibria (e.g., enol/ketone, formic acid, formamidine, etc.), and section 4.2.3 will discuss an example of a ring/chain tautomeric equilibrium. The order of presentation will be approximately by increasing molecular weight within each section. A review by Kwiatkowski et al. [267] covers work on formamide, pyridines, pyrimidines, purines, and nucleic... 

Figure 3. Variations of the tautomerism equilibrium constant Kr ([B] = 0.3 mole l 1, 30°C) of t-butyl-2-picolyl (0) and quinaldyl (A) ketones vs. solvent polarity. (DME) dimethoxyethane (CFG) propyleneglycol carbonate (NMF) N-methylformamide (F)formamide.

Nitroalkanes react with Jt-deficient alkenes, for example, p-nitro ketones are produced from a,P-unsaturated ketones [41], whereas allylic nitro compounds have been prepared via the Michael-type addition of nitroalkanes with electron-deficient alkynes (Table 6.19). The reaction in either dimethylsulphoxide [42] or dimethyl-formamide [43] is catalysed by potassium fluoride in the presence of benzyltriethyl-ammonium chloride the reaction with dimethyl acetylenedicarboxylate is only successful in dimethylsulphoxide [42], Primary nitroalkanes produce double Michael adducts [42,44], A-Protected a-aminoacetonitriles react with alkynes under catalysed solidiliquid conditions to produce the Michael adducts [45] which, upon treatment with aqueous copper(Il) sulphate, are converted into a,p-unsaturated ketones. 

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