Carboxylic add chlorides

Amine 212 was also coupled with peptides [233], acetic anhydride [215, 234], dinitrobenzoyl chloride [235] or a ferrocene carboxylic add chloride [215, 236] in good yields. Reaction with dinitrochlorobenzene [237] or dinitrofluorobenzene... 

Answer Procedure IX-6 requiring a carboxylic add chloride and a salt of a carboxylic acid. 

Formation of the carboxylic add chloride, e.g. with thionyl chloride or with phosphorus pentachloride. 

A final method for the preparation of pyrido[2,3-[Pg.229]

Identity the carboxylic add chloride that might be used in a Friedel-Crafts acylation reaction to prepare each of the following acylbenzenes ... 

Condensation of thiophene-3-carbaldehyde 38 with malonic acid (Doebner reaction) in a mixture of pyridine (Py) and piperidine (Hp) with heating affords ( )-3-(3-thienyl)acrylic add (42), whose treatment with thionyl chloride in Py produces 3-chlorothieno[2,3-6]thiophene-2-carboxylic add chloride (43) (72ACS2982,... 

JHC1363). Analogously, 3,5-dichlorothieno[3,2-6]-2-carboxylic add chloride was prepared from thiophene-2-carbaldehyde (72ACS2982, 72JHC879, 88JHC1363). 

Dichlorothieno[2, 3 4,5]thieno[2,3-c]quinolme (203) was synthesized from 3,5-dichlorothieno[3,2-fe]thiophene-2-carboxylic add chloride (202). Catalytic dechlorination of 203 afforded unsubstituted thieno[2, 3 4,5]thieno[2,3-c]quinoline (204) (88JHC1363). 

Hydroxamic acids from carboxylic add chlorides COCl -> CONHOH... 

Three types of lubricants which possess both the perfluoroalkyl group and hydrocarbon long chain, that is an ester, amide, and carboxylic acid amine salt, were synthesized by the following Scheme 1 in Fig.4. The ester and the amide were prep>ared by the addition of carboxylic add chloride to the hexane solution of the corresponding alcohol and amine in the presence of a base agent. The perfluorocarboxylic add and the carboxyhc add ammonium salts are prepared by warming the mixture of the perfluorocarboxylic add and the amine to 80°C imtil the complete dissolution was obtained (Scheme 2).(Kondo et al., 1989,1994)... 

Carboxylic add chlorides Even though several copolymerization reactions of carboxylic adds have been reported, only one publication on the copolymerization of carboxylic add chlorides and a-olefins can be fotmd in literature. Kay et al observed the copolymerization of propene with 10-tmdecenoyl chloride using rac-Et(lnd)2ZrCl2/MAO. This copolymetiza-tion reaction exhibits a lower activity, molecular weight, and comonomer content in the polymer compared to the conesponding carboxylic add. 

Names ending in -carbonsdure are translated -carboxylic add, not -carbonic acid (but -carbonyl chloride is preferred to -carboxylyl chloride). 

Electronically, we find that strongly polarized acyl compounds react more readily than less polar ones. Thus, acid chlorides are the most reactive because the electronegative chlorine atom withdraws electrons from the carbonyl carbon, whereas amides are the least reactive. Although subtle, electrostatic potential maps of various carboxylic add derivatives indicate the differences by the relative blueness on the C-O carbons. Acyl phosphates are hard to place on this scale because they are not used in the laboratory, but in biological systems they appear to be somewhat more reactive than thioesters. 

Acid anhydrides are typically prepared by nucleophilic acyl substitution reaction of an add chloride with a carboxylate anion, as we saw in Section 21.4. Both symmetrica] ancl unsymmetrical acid anhydrides can be prepared in this way. 

Conversion of Amides into Carboxylic Acids Hydrolysis Amides undergo hydrolysis to yield carboxylic acids plus ammonia or an amine on heating in either aqueous acid or aqueous base. The conditions required for amide hydrolysis are more severe than those required for the hydrolysis of add chlorides or esters but the mechanisms are similar. Acidic hydrolysis reaction occurs by nucleophilic addition of water to the protonated amide, followed by transfer of a proton from oxygen to nitrogen to make the nitrogen a better leaving group and subsequent elimination. The steps are reversible, with the equilibrium shifted toward product by protonation of NH3 in the final step. 

An acid chloride is a deriva live of a carboxylic add in which the hydroxyl group is replaced by a chlorine atom. 

Conversions of carboxylic acids to ketones are typically performed in stepwise fashion6 via intermediates such as acid chlorides,7 anhydrides,8 thioesters,9 or N-alkoxy amides,10 or by the direct reaction of carboxylic adds with lithium reagents.11 In this latter method trimethylsifyl chloride has been shown to be an effective reagent for trapping the tetrahedral alkoxide intermediates and for quenching excess organolithium reagent. 

Protected-amino phosphonic acid monoesters 51 are usually activated by conversion to the phosphonochloridates 52, then coupled with appropriate amine components such as C-protected amino adds or peptides to give phosphonoamidates 53 (Scheme 17). This procedure is in contrast to typical peptide coupling conditions, in which carboxylic acid chlorides are avoided because of their susceptibility to epimerization at the a-carbon. Since enolate-... 

Alkyl-l-(2-hydroxyethyl)-2-imidazolines are used in hydrocarbon and aqueous systems as antistatic agents, corrosion inhibitors, detergents, emulsifiers, softeners, and viscosity builders They are prepared by heating the salt of a carboxylic add with (2-hvdroxyethyl) ethylenediamine at 150-160cC to form a substituted amide 1 mol water is eliminated to form the substituted imidazoline with further heating at 180-200, C. Substituted imidazolines yield three series of cationic surfactants by ethoxylation to form more hydrophilic, products quaternization with benzyl chloride, dimethyl sulfate, and other alkyl halides and oxidation with hydrogen peroxide to amine oxides,... 

Carboxy terminal amino acid or peptide thiols are prepared from various p-amino alcohols by conversion into a thioacetate (R2NHCHR1CH2SAc) via a tosylate followed by saponification.Several methods have been used to prepare N-terminal peptide thiols, the most common procedure is the coupling of (acetylsulfanyl)- or (benzoylsulfanyl)alkanoic acids or add chlorides with a-amino esters or peptide esters, followed by deprotection of the sulfanyl and carboxy groups. 8 16 Other synthetic methods include deprotection of (trit-ylsulfanyl)alkanoyl peptides, 1718 alkaline treatment of the thiolactones from protected a-sulfanyl acids, 19 and preparation of P-sulfanylamides (HSCH2CHR1NHCOR2, retro-thior-phan derivatives) from N-protected amino acids by reaction of P-amine disulfides with carboxylic acid derivatives, followed by reduction. 20,21 In many cases, the amino acid or peptide thiols are synthesized as the disulfides and reduced to the corresponding thiols by the addition of dithiothreitol prior to use. 

Carboxylic acid chlorides and chloroformate esters add to tetrakis(triphenylphosphine)palladium(0) to form acylpalladium derivatives (equation 42).102 On heating, the acylpalladium complexes can lose carbon monoxide (reversibly). Attempts to employ acid halides in vinylic acylations, therefore, often result in obtaining decarbonylated products (see below). However, there are some exceptions. Acylation may occur when the alkenes are highly reactive and/or in cases where the acylpalladium complexes are resistant to decarbonylation and in situations where intramolecular reactions can form five-membered rings. 

The Yatmguchi procedure constitutes another m-situ approach to the activation of carboxylic adds. Ileie the activated species is a mixed anhydride formed with trichlorobenzoic acid chloride (see Chapter 6). 

Acid chlorides are the most reactive of the carboxylic add derivatives. Add chlorides love nucleophiles. 

C is correct. Inorganic add chlorides react with carboxylic acids by nucleophilic substitution to form acyl clorides you should memorize this reaction. 

What procedure is available Tor the preparation of amides Answer Procedure IX-7, which requires a carboxylic acid chloride cleaved from the add portion of the amide and an amine. Thus, for IX-b we need the acid diloridc C and the amine B. 

Accordingly, if one wants to react a nucleophile and carboxylic acid derivative to produce a carbonyl compound in a chemoselective fashion according to the mechanism of Figure 6.2, then one best employs carboxylic acid chlorides or comparably strongly activated carboxylic acid derivatives. In addition, the respective reaction must be carried out with the weakest possible nucleophile because only such a nucleophile reacts considerably faster with the activated carboxylic add derivative than with the product carbonyl compound (see above). The nucleophile must react considerably faster with the carboxylic acid derivative because at 95% conversion there is almost twenty times more carbonyl compound present than carboxylic acid derivative, but even at this stage the carboxylic acid derivative must be the preferred reaction partner of the nucleophile. 

Poly(carboxylic add)s Poly(4-vinylbenzyl-trimethylammonium chloride) 142,143... 

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