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Oxalyl

The reaction giving A is chloromethylation, a reliable metliod of adding a CH2OH equivalent to an aromatic ring. You may have been surprised at the use of reagent B to make an acid chloride. B is oxalyl chloride and is often used when pure acid chlorides are wanted - the other products are gases (which ). [Pg.25]

The widely used Moifatt-Pfltzner oxidation works with in situ formed adducts of dimethyl sulfoxide with dehydrating agents, e.g. DCC, AcjO, SO], P4O10, CCXTl] (K.E, Pfitzner, 1965 A.H. Fenselau, 1966 K.T. Joseph, 1967 J.G. Moffatt, 1971 D. Martin, 1971) or oxalyl dichloride (Swem oxidation M. Nakatsuka, 1990). A classical procedure is the Oppenauer oxidation with ketones and aluminum alkoxide catalysts (C. Djerassi, 1951 H. Lehmann, 1975). All of these reagents also oxidize secondary alcohols to ketones but do not attack C = C double bonds or activated C —H bonds. [Pg.133]

Oxalyl chloride reacts at 25°Cin tetrahydrofuran with 2-amino-5-nitro-thiazole. yielding structure 98 (Scheme 68) (261). [Pg.50]

Exceptions formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl, oxalyl, malonyl, succinyl, glutaryl, furoyl, and thenoyl. [Pg.30]

Fluorinated ether-containing dicarboxyhc acids have been prepared by direct fluorination of the corresponding hydrocarbon (17), photooxidation of tetrafluoroethylene, or by fluoride ion-cataly2ed reaction of a diacid fluoride such as oxalyl or tetrafluorosuccinyl fluorides with hexafluoropropylene oxide (46,47). Equation 8 shows the reaction of oxalyl fluoride with HEPO. A difunctional ether-containing acid fluoride derived from HEPO contains regular repeat units of perfluoroisopropoxy group and is terminated by two alpha-branched carboxylates. [Pg.312]

Preparation of Arylcarboxylic Acids and Derivatives. The general Friedel-Crafts acylation principle can be successfully appHed to the preparation of aromatic carboxyUc acids. Carbonyl haUdes (phosgene, carbonyl chloride fluoride, or carbonyl fluoride) [353-50-4] are diacyl haUdes of carbonic acid. Phosgene [75-44-5] or oxalyl chloride [79-37-8] react with aromatic hydrocarbons to give aroyl chlorides that yield acids on hydrolysis (133) ... [Pg.560]

Acylation. Acylation is the most rehable means of introducing a 3-substituent on the indole ring. Because 3-acyl substituents can be easily reduced to 3-aLkyl groups, a two-step acylation—reduction sequence is often an attractive alternative to direct 3-aLkylation. Several kinds of conditions have been employed for acylation. Very reactive acyl haUdes, such as oxalyl chloride, can effect substitution directiy without any catalyst. Normal acid chlorides are usually allowed to react with the magnesium (15) or 2inc (16) salts. The Vilsmeier-Haack conditions involving an amide and phosphoms oxychloride, in which a chloroiminium ion is the active electrophile, frequentiy give excellent yields of 3-acylindoles. [Pg.85]

Specialty Isocyanates. Acyl isocyanates, extensively used in synthetic appHcations, caimot be direcdy synthesized from amides and phosgene. Reactions of acid haUdes with cyanates have been suggested. However, the dominant commercial process utilizes the reaction of carboxamides with oxalyl chloride [79-37-8]. CycHc intermediates have been observed in these reactions which generally give a high yield of the desired products (86). [Pg.456]

Commercially important arenesulfonyl isocyanates are not directly accessible from the corresponding sulfonamides via phosgenation due to lack of reactivity or by-product formation at elevated temperatures. A convenient method for their preparation consists of the reaction of alkyl isocyanates with sulfonamides to produce mixed ureas which, upon phosgenation, yield a mixture of alkyl and arenesulfonyl isocyanates. The desired product can be obtained by simple distillation (16). Optionally, the oxalyl chloride route has been employed for the synthesis of arenesulfonyl isocyanate (87). [Pg.456]

Oxahc acid reacts with various metals to form metal salts, which are quite important as the derivatives of oxahc acid. It also reacts easily with alcohols to give esters. Crystalline dimethyl oxalate is, for example, produced by the reaction of oxahc acid dihydrate and methanol under reflux for a few hours. When oxahc acid is treated with phosphoms pentachloride, oxalyl chloride, ClCOCOCl, is formed (6). [Pg.457]

Oxalyl Chloride. This diacid chloride [79-37-8], ClCOCOCl, mol wt 126.9, is produced by the reaction of anhydrous oxaUc acid and phosphoms pentachloride. The compound vigorously reacts with water, alcohols, and amines, and is employed for the synthesis of agrochemicals, pharmaceuticals, and fine chemicals. [Pg.463]

Fluoroformyl peroxide [692-74-0] (20, R = R = F), has been prepared by the reaction of carbon monoxide, fluorine, and oxygen or by the photolytic reaction of oxalyl fluoride with oxygen (187). [Pg.125]

Sorbic acid anhydride [13390-06-2] can be prepared by heating the polyester of 3-hydroxy-4-hexenoic acid with sorboyl chloride [2614-88-2] or by reaction of sorbic acid with oxalyl chloride (15,16). Preparation of the esters of sorbic acid must be controlled to prevent oxidation and polymerization. The lower sorbic acid esters have a pleasant odor. [Pg.282]

Examples of commercial metal deactivators used in polymers, gasoline, and foods are oxalyl bis(bensyhdene)hydraside [6629-10-3] (28). [Pg.228]

The stabili2ation of polyolefins used to insulate copper conductors requires the use of a long-term antioxidant plus a copper deactivator. Both A[,Ar-bis(3,5-di-/ A-butyl-4-hydroxycinnamoyl)hydra2ine (29) and 2,2 -oxamidobisethyl(3,5-di-/ A-butyl-4-hydroxycinnamate) (30) are bifimctional. They are persistent antioxidants that have built-in metal deactivators. Oxalyl bis(ben2yhdenehydra2ide) (28) is an effective copper deactivator when part of an additive package that includes an antioxidant. [Pg.232]

Cl Vat YeUow 12 is prepared by condensing l-anaino-5-ben2oylaininoanthraquinone [117-06-6] (161) with oxalyl chloride in nitroben2ene. Cl Vat YeUow 33 is prepared by condensation of two moles of 1-aminoanthraquinone with one mole of 4V -a2obis(4-biphenylcarbonyl chloride). Cl Vat Red 21 is prepared from 1,4-diaminoanthraquinone (33) and l-nitroanthraquinone-2-carboxyhc acid (58) by the foUowing process ... [Pg.331]

Because of the structural requirements of the bielectrophile, fully aromatized heterocycles are usually not readily available by this procedure. The dithiocarbamate (159) reacted with oxalyl chloride to give the substituted thiazolidine-4,5-dione (160) (see Chapter 4.19), and the same reagent reacted with iV-alkylbenzamidine (161) at 100-140 °C to give the 1 -alkyl-2-phenylimidazole-4,5-dione (162) (see Chapter 4.08). Iminochlorides of oxalic acid also react with iV,iV-disubstituted thioureas in this case the 2-dialkylaminothiazolidine-2,4-dione bis-imides are obtained. Thiobenzamide generally forms linear adducts, but 2-thiazolines will form under suitable conditions (70TL3781). Phenyliminooxalic acid dichloride, prepared from oxalic acid, phosphorus pentachloride and aniline in benzene, likewise yielded thiazolidine derivatives on reaction with thioureas (71KGS471). [Pg.129]

Of particular interest is the reaction of 5,5-disubstituted sulfur diimides (188) with oxalyl chloride in dilute solution in the presence of triethylamine. The l,2,5-thiadiazole-3,5-dione (189) was formed in almost quantitative yield (72LA(759)107). [Pg.131]

The aziridinecarboxylate (177) undergoes ring expansion in good yield, possibly via a mixed anhydride, on treatment with thionyl or oxalyl chlorides in benzene (69JA4590). [Pg.262]


See other pages where Oxalyl is mentioned: [Pg.370]    [Pg.143]    [Pg.325]    [Pg.113]    [Pg.125]    [Pg.126]    [Pg.56]    [Pg.483]    [Pg.709]    [Pg.709]    [Pg.709]    [Pg.101]    [Pg.321]    [Pg.476]    [Pg.267]    [Pg.119]    [Pg.126]    [Pg.70]    [Pg.283]    [Pg.141]    [Pg.263]    [Pg.700]    [Pg.230]    [Pg.378]    [Pg.118]    [Pg.129]    [Pg.145]    [Pg.146]   


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3-N‘Oxalyl

4-Hydroxyquinoline-2-one, reaction with oxalyl chloride

A-Chloroacetamide, reaction with oxalyl

A-Chloroacetamide, reaction with oxalyl isocyanate

Acid chlorides oxalyl chloride/DMSO

Acid using oxalyl chloride

Acyl chlorides oxalyl chloride

Alkenes oxalyl chloride

Alkyl oxalyl chlorides, reactions

Amides oxalyl

Amides reaction with oxalyl chloride

Amines oxalyl chloride

Aromatic polyamides and polyhydrazides containing the oxalyl group

Aromatics complexes with oxalyl chloride

Benzo with oxalyl chloride

Carboxylic acid anhydrides oxalyl chloride

Carboxylic acid chloride synthesis, oxalyl

Carboxylic acid chlorides oxalyl chloride

Carboxylic acid chlorides oxalyl chloride-dimethylformamide

Carboxylic acids reaction with oxalyl chloride

Chemoluminescence with Oxalyl Chloride

Chloride oxalyl, reaction with

Chlorinations oxalyl chloride

Cycloaddition reactions oxalyl chloride

DAMN with Oxalyl Chloride

Diaryl with oxalyl chloride

Dimethyl sulfoxide reaction with oxalyl chloride

Dimethyl sulfoxide-Oxalyl chloride

Dimethylformamide-Oxalyl chloride

Equilenin ketone oxalylation

Esterification with oxalyl chloride

Ethyl oxalyl chloride

Formylations oxalyl chloride-dimethylformamide

Friedel Crafts with oxalyl chloride

Friedel oxalyl chloride

Indoles with oxalyl chloride

Isocyanates, acyl, derivatives preparation using oxalyl chloride

Malonic acid dibromide via oxalyl bromide

Mandelic acid, hexahydrosynthesis ketone oxalylation

Methyl oxalyl chloride

Oxalyl Chloride reactions with carbonyl groups

Oxalyl Chloride related reagents

Oxalyl Dichloride

Oxalyl amide compounds

Oxalyl as reagent

Oxalyl bromide

Oxalyl bromide chloride

Oxalyl chlonde, Fnedel-Crafts

Oxalyl chlonde, Fnedel-Crafts synthesis

Oxalyl chloride

Oxalyl chloride , reduction with

Oxalyl chloride /DMF

Oxalyl chloride DMSO oxidation of alcohols

Oxalyl chloride Oxime

Oxalyl chloride Swern oxidation

Oxalyl chloride acid halide synthesis

Oxalyl chloride activator

Oxalyl chloride alcohol oxidation

Oxalyl chloride chlorides

Oxalyl chloride decomposition

Oxalyl chloride in preparation of acid chlorides

Oxalyl chloride isocyanates

Oxalyl chloride products using

Oxalyl chloride reaction

Oxalyl chloride reaction with anthracene

Oxalyl chloride reactions with alkanes

Oxalyl chloride, 1,3-cycloaddition

Oxalyl chloride, DMSO activator

Oxalyl chloride, Stolle reaction

Oxalyl chloride, and DMSO

Oxalyl chloride, condensation, with

Oxalyl chloride, ethylFriedel-Crafts reaction

Oxalyl chloride, peroxyoxalate

Oxalyl chloride, peroxyoxalate chemiluminescence

Oxalyl chloride, reaction with a-chloroacetamide

Oxalyl chloride, reaction with acids

Oxalyl chloride-Sodium iodide

Oxalyl chloride: Ethanedioyl dichloride

Oxalyl chloride: reaction with carboxylic

Oxalyl cyanide

Oxalyl derivatives

Oxalyl dibromide

Oxalyl dihalides

Oxalyl dimethylformamide

Oxalyl ethyl ester Azide

Oxalyl glycine

Oxalyl group

Oxalyl halides

Oxalyl linkage

Oxalyl ring closures with

Oxalyl urea

Oxalyl-2,3-diaminopropionic acid

Oxalyl-acetic ester

Oxalylation

Oxalylation ketones

Phosgene oxalyl chloride

Phosphonic acid chlorides oxalyl chloride

Radical Carboxylation with Methyl Oxalyl Chloride

Reagents oxalyl chloride

Swem oxidant with oxalyl chloride

Using a Diacyl Dihalide (Oxalyl Halide) or Related Synthon

With oxalyl fluoride

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