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Amines oxalyl chloride

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]

Many procedures for the formation of carboxylic acid amides are known in the literature. The most widely practiced method employs carboxylic acid chlorides as the electrophiles which react with the amine in the presence of an acid scavenger. Despite its wide scope, this protocol suffers from several drawbacks. Most notable are the limited stability of many acid chlorides and the need for hazardous reagents for their preparation (thionyl chloride, oxalyl chloride, phosgene etc.) which release corrosive and volatile by-products. Moreover, almost any other functional group in either reaction partner needs to be protected to ensure chemoselective amide formation.2 The procedure outlined above presents a convenient and catalytic alternative to this standard protocol. [Pg.137]

The traditional method for transforming carboxylic acids into reactive acylating agents capable of converting alcohols to esters or amines to amides is by formation of the acyl chloride. Molecules devoid of acid-sensitive functional groups can be converted to acyl chlorides with thionyl chloride or phosphorus pentachloride. When milder conditions are necessary, the reaction of the acid or its sodium salt with oxalyl chloride provides the acyl chloride. When a salt is used, the reaction solution remains essentially neutral. [Pg.243]

Acyl hydrazides are useful precursors for the synthesis of 1,2,4-triazoles. Reaction of acyl hydrazides 149 with imidoylbenzotriazoles 148 in the presence of catalytic amounts of acetic acid under microwave irradiation afforded 3,4,5-trisubstituted triazoles 150 <06JOC9051>. Treatment of A-substituted acetamides with oxalyl chloride generated imidoyl chlorides, which reacted readily with aryl hydrazides to give 3-aryl-5-methyl-4-substituted[ 1,2,4]triazoles <06SC2217>. 5-Methyl triazoles could be further functionalized through a-lithiation and subsequent reaction with electrophiles. ( )-A -(Ethoxymethylene)hydrazinecarboxylic acid methyl ester 152 was applied to the one-pot synthesis of 4-substituted-2,4-dihydro-3//-1,2,4-triazolin-3-ones 153 from readily available primary alkyl and aryl amines 151 <06TL6743>. An efficient synthesis of substituted 1,2,4-triazoles involved condensation of benzoylhydrazides with thioamides under microwave irradiation <06JCR293>. [Pg.231]

FIGURE 7.18 Preparation of Fmoc-amino-acid chlorides by reaction (A) of thionyl chloride,47 phosgene from triphosgene,54 l-chloro-2,A7,A7-trimethyl-l-propene- 1-amine, [Schmidt et al., 1988] or oxalyl chloride, [Rodriguez, 1997] with the parent acid and (B) of hydrogen chloride with the mixed anhydride.51... [Pg.214]

Diethyl 7V-(t-butoxycarbonyl)phosphoramidate 18 is obtained from diethyl phospho-ramidate by successive treatment with oxalyl chloride and t-butyl alcohol. It forms a stable non-hydroscopic sodium salt, which reacts with a variety of alkyl halides in benzene in the presence of tetrabutylammonium bromide under phase-transfer conditions to give the corresponding TV-alkyl derivatives. The latter are cleaved by hydrogen chloride in benzene to yield amine hydrochlorides (equation 16)48. [Pg.540]

The carboxylic functionalities inserted onto the tubes can be used as platforms to obtain further transformations (Fig. 3.5). A commonly utilized route is the reaction of carboxylic groups with thionyl chloride or oxalyl chloride to prepare the corresponding acyl chlorides, which are useful intermediates for amidation or esterification reactions. Amides can also be prepared directly from the acids by means of standard solution chemistry conditions, using carbodiimide derivatives in the presence of the selected amine. [Pg.48]

There are several chemical reactions that can be used as an alternative to achieve covalent functionalization of CNTs. Two of them are amidation and/or esterification reactions. Both reactions take advantage of the carboxylic groups sitting on the side-walls and tips of CNTs. In particular, they are converted to acyl chloride groups (-C0-C1) via a reaction with thionyl (SO) or oxalyl chloride before adding an alcohol or an amine. This procedure is very versatile and allows the functionalization of CNTs with different entities such as biomolecules [154-156], polymers [157], and organic compounds [158,159] among others. [Pg.82]

The 7-lactam 120, which is very reactive, is obtained from the reaction of methyl 2-(2-methoxycarbonylmethyl-ene)-5-methyl-3,6-dihydro-2//-l,3-thiazine-4-carboxylate 119 with oxalyl chloride and in the presence of triethyl-amine (Scheme 5). Subsequent treatment with methanol affords 3,6-dihydro-2//-l,3-thiazine 121 as a mixture of isomers. Similar treatment of the 4-allyl carboxylate analogue with oxalyl chloride/triethylamine yielded the corresponding 7-lactam <1999J(P1)2449>. [Pg.580]

Replacement of the chlorine in 487b with isopropylamine is accomplished, then the secondary amine product is acylated with ethyl oxalyl chloride (Equation 184). Again reduction of the nitro group allows cyclization to 489 to occur <2001H(55)1963>. [Pg.416]

I. N,N-Dimethyllsobutyramide (Gavrilov, N., Koperina, A. Klutcharova, M. Hull. Sao. Chim. France 1945, 12, 773) was converted to l-chloro-N,N,2-lHim-1hy1propenylamine according to the procedure of Ovg. Synth. 1979, 59, 26, in n17 yield, bp 118-121°C. Freshly-distilled oxalyl chloride was used Iii.iimiI of phosgene. The propenyl amine should be handled carefully in a vyi Inqi In avoid its rapid hydrolysis by moisture. [Pg.117]

There is the raw stuff potentially available to answer this question. There are a couple of compounds known with the sulfur in the 4-position, which is the location of the oxygen atom in psilocybin. The 4-thio analogues have been synthesized from 4-methylthio-indole, via the oxalyl chloride method and reaction with the appropriate amine. With dimethylamine, the indoleglyoxylamide was made in a 43% yield and had a mp 163-164 °C. With diisopropylamine, the amide was made in a 27% yield and had a mp 190-192 °C. The final amines were prepared by the reduction of these amides with LAH in THF. N,N-Dimethyl-4-thiotryptamine (4-MeS-DMT) was obtained in a 68% yield and melted at 108-110 °C N,N-diisopropyl-4-methylthiotryptamine (4-MeS-DIPT) was obtained in a 61% yield and melted at 92-94 °C. In animal studies of behavioral disruption with these three compounds, there was systematic drop of potency in going from the 5-MeS-DMT to 4-MeS-DMT to 4-MeS-DIPT. [Pg.229]

EXTENSIONS AND COMMENTARY N-Methyltryptamine (monomethyltryptamine, NMT) is an alkaloid that has been found in the bark, shoots and leaves of several species of Virola, Acacia and Mimosa. However, the major snuffs associated with these plant have been shown to also contain 5-MeO-DMT and are discussed there. NMT has been synthesized in a number of ways. One can react 3-(2-bromoethyl)indole with methylamine. NMT can be isolated as the benzoyl derivative from the methylation of tryptamine with methyl iodide followed by reaction with benzoyl chloride, with the hydrolysis of this amide with alcoholic KOH. It can also be synthesized from indole with oxalyl chloride, with the resulting glyoxyl chloride reacting with methylamine in ether to give indol-3-yl N-methylglyoxalylamide (mp 223-224 °C from IPA) which is obtained in a 68% yield, which is reduced to NMT to give the amine hydrochloride (mp 175-177 °C from ) in a 75% yield. The most simple and direct synthesis is the formamide reduction given above. [Pg.246]

Primary amines at a primary carbon can be dehydrogenated to nitriles. The reaction has been carried out with a variety of reagents, among others, IF5,"9 lead tetraacetate, 20 nickel peroxide,121 NaOCl in micelles,122 S g-NiSO, 2-1 and CuCl-02-pyridine.124 Several methods have been reported for the dehydrogenation of secondary amines to imines.125 Among them126 are treatment with(l) iodosylbenzene PhIO alone or in the presence of a ruthenium complex, 27 (2) Me2SO and oxalyl chloride, 2" and (3) f-BuOOH and a rhenium catalyst. 29... [Pg.1172]

In a detailed study on phosphonate diester and phosphonamidate synthesis, Hirschmann, Smith, and co-workers reported that pyrophosphonate anhydrides may be produced as side products during conversion of phosphonate monoesters into phosphonochloridates. 72 They recommended adding the phosphonate monoester to a solution of the chlorinating agent (thionyl chloride or oxalyl chloride) to minimize formation of the less reactive anhydrides. They also found that addition of tertiary amines (e.g., TEA) to the phosphonochloridates, prior to addition of the alcohol or amine component, results in formation of a phospho-nyltrialkylammonium salt that is more reactive than the corresponding phosphonochloridate and leads to better yields of the phosphonate esters and amides. [Pg.512]

Diazalithioacetone. Dimethylaluminum benzenethiolate. Dimethylsulfoxide-Oxalyl chloride. Hydroxy (amine. Zinc chloride. [Pg.650]

Acylation, of amines with f-butyl azidoformate, 44, 17 of enamines by add halides, 43, 34 of ethyl acetoacetate by y-carbeth-oxybutyryl chloride, 42, 41 of mesitylene with oxalyl chloride, 44, 69... [Pg.105]


See other pages where Amines oxalyl chloride is mentioned: [Pg.143]    [Pg.125]    [Pg.283]    [Pg.46]    [Pg.1518]    [Pg.61]    [Pg.342]    [Pg.142]    [Pg.416]    [Pg.48]    [Pg.267]    [Pg.848]    [Pg.1095]    [Pg.266]    [Pg.11]    [Pg.72]    [Pg.363]    [Pg.105]    [Pg.113]    [Pg.129]    [Pg.131]    [Pg.137]    [Pg.210]    [Pg.240]    [Pg.164]    [Pg.6]    [Pg.512]    [Pg.143]    [Pg.337]    [Pg.180]   
See also in sourсe #XX -- [ Pg.16 , Pg.502 ]




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Oxalyl

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