Alkyl with carboxylates

Radical alkylation and carbamoylation of 4-cyanopyridine (54) have been reported. (54) has been alkylated with carboxylic acids, using trivalent iodine compounds as oxidant, to give (65) (Scheme 32) (93JCS(P1)2417>. (54)... 

N-Alkylation with carboxylic acid esters NH N-CHgCN... 

Sodium tetrahydridoborate Reductive N-alkylation with carboxylic acids of N-heterocyclics... 

Ethers of benzenepentol have been obtained by Dakin oxidation of the appropriately substituted acetophenone. Thus, the oxidation of 2-hydroxy-3,4,6-ttimethoxyacetophenone and 2-hydroxy-3,4,5-ttimethoxyacetophenone with hydrogen peroxide ia the presence of alkali gives l,2-dihydroxy-3,4,6-ttimethoxybenzene and l,2-dihydroxy-3,4,5-ttimethoxybenzene, respectively further methylation of these ethers yields the pentamethyl ether of benzenepentol (mp 58—59 degC) (253). The one-step aromatization of myoinositol to produce esters of pentahydroxybenzene is achieved by treatment with carboxylic acid anhydrides ia DMSO and ia the presence of pyridine (254) (see Vitamins). 6-Alkyl- or... 

During electrochemical fluorination retention of important functional groups or atoms in molecules is essential. Acyl fluorides and chlorides, but not carboxylic acids and anhydrides (which decarboxylate), survive perfluorination to the perfluorinated acid fluorides, albeit with some cyclization in longer chain (>C4) species [73]. Electrochemical fluorination of acetyl fluoride produces perfluoro-acetyl fluoride in 36-45% yields [85]. Electrochemical fluorination of octanoyl chloride results in perfluorinated cyclic ethers as well as perfluorinated octanoyl fluonde. Cyclization decreases as initial substrate concentration increases and has been linked to hydrogen-bonded onium polycations [73]. Cyclization is a common phenomenon involving longer (>C4) and branched chains. a-Alkyl-substituted carboxylic acid chlorides, fluorides, and methyl esters produce both the perfluorinated cyclic five- and six-membered ring ethers as well as the perfluorinated acid... 

Photochemically induced reduction of alkyl perfluoro carboxylates in hexa-methylphosphoramide (FfMPA) can replace one, two, or (in the case of tn-fluoroacetate) three a-fluonne atoms with hydrogen [7, S] (equation 5) Chlorine-containing fluorocarboxylates preferentially lose a-chlorme and may even lose P-chlorinc in preference to a fluonne [9] (equation 6) Cyclic a-fluoroketones are also defluonnated photochemically [10] (equation 7)... 

Polyfluorinated a-diketones react with 1,2-diainino compounds, such as ortlio-phenylenediamine, to give 2,3-substituted quinoxalmes [103] Furthermore, the carboxyl function of trifluoropyruvates offers an additional electrophilic center. Cyclic products are obtained with binucleophiles [13, 104] With aliphatic or aromatic 1,2-diamines, six-memhered heterocycles are formed Anilines and phenols undergo C-alkylation with trifluoropyruvates in the ortho position followed by ring closure to form y-lactams and y-lactones [11, 13, 52, 53, 54] (equation 23). 

Perhydropyrido[l,2-a]pyrimidin-2-one was A -alkylated with 1,4-dibro-mobutane to yield a 1-(4-bromobutyl) derivative (94MIP6). 6-Methyl-4-oxo-4/f-],6,7,8,9,9a-hexahydro-4//-pyrido[],2-a]pyrimidine-3-carboxylate 138 was alkylated with alkyl chlorides 139 to give 1-substituted derivatives 140 (97MIP2). 

The hydroxy group of ethyl 9-hydroxy-4-oxo-4//-pyrido[l,2-u]pyrimi-dine-3-carboxylate was O-alkylated with 2-chloromethyl-4-isopropyl-l,... 

Alpha hydrogen atoms of carbonyl compounds are weakly acidic and can be removed by strong bases, such as lithium diisopropylamide (LDA), to yield nucleophilic enolate ions. The most important reaction of enolate ions is their Sn2 alkylation with alkyl halides. The malonic ester synthesis converts an alkyl halide into a carboxylic acid with the addition of two carbon atoms. Similarly, the acetoacetic ester synthesis converts an alkyl halide into a methyl ketone. In addition, many carbonyl compounds, including ketones, esters, and nitriles, can be directly alkylated by treatment with LDA and an alkyl halide. 

Examples of polyfunctional carboxylic acids esterified by this method are shown in Table I. Yields are uniformly high, with the exception of those cases (maleic and fumaric acids) where some of the product appears to be lost during work-up as a result of water solubility. Even with carboxylic acids containing a second functional group (e.g., amide, nitrile) which can readily react with the oxonium salt, the more nucleophilic carboxylate anion is preferentially alkylated. The examples described in detail above illustrate the esterification of an acid containing a labile acetoxy group, which would not survive other procedures such as the traditional Fischer esterification. 

The procedure described here illustrates the preparation of mixed lithium arylhetero(alkyl)cuprate reagents and their reactions with carboxylic acid chlorides,4 These mixed cuprate reagents also react with a,a -dibromoketones,12 primary alkyl halides,4 and a,/3-unsaturated ketones,4 with selective transfer of only the alkyl group. 

The reaction of tert-alkyl Grignard reagents with carboxylic acid chlorides in the presence of a copper catalyst provides ieri-alkyl ketones in substantially lower yields than those reported here.4,14 The simplicity and mildness of experimental conditions and isolation procedure, the diversity of substrate structural type, and the functional group selectivity of these mixed organocuprate reagents render them very useful for conversion of carboxylic acid chlorides to the corresponding secondary and tertiary alkyl ketones.15... 

Phenolic compounds are weaker nucleophiles and better leaving groups than aliphatic alcohols. They do not yield polyesters when reacted with carboxylic acids or alkyl carboxy lates. The synthesis of polyesters from diphenols is, therefore, generally carried out through the high-temperature carboxylic acid-aryl acetate or phenyl ester-phenol interchange reactions with efficient removal of reaction by-product (Schemes 2.10 and 2.11, respectively). 

From the apparent ionization degree it was concluded that the EO chain probably behaves as part of the headgroup. As with Aalbers [49], a low surface charge of the sodium alkyl ether carboxylate micelles was mentioned. The micelle aggregation number N increases with the C chain much more than for the corresponding nonionic surfactants. In the case of C8 there was no influence of temperature. A small decrease was found with increasing EO, but much smaller than in the case of nonionics. 

In a patent survey [76] about shampoos over the period 1968-1978 the so-called cryptoanionic alkyl ether carboxylate based on tridecyl alcohol with 6.5 mol EO has been mentioned for a conditioning shampoo in combination with an amphoteric and cationic surfactant [77]. Because of the low interference with cationic surfactants no negative effect on the conditioning properties has been found [78]. 

In combination with alkyl ether sulfates, a synergistic decrease of the irritation level of the ether sulfates and an improvement of the foam stabilization has been described [57,67,78]. A good compromise between mildness and foam properties could be achieved with lauryl ether carboxylic acid sodium salt with 10 mol EO [57,67]. In several articles examples of the use of alkyl ether carboxylates as cosurfactant in mild shampoos as well as bath and shower products have been described [57,69,79]. 

The reaction product with monoethanolamine acts as a thickening agent [41,101] and with alcohols as an emollient [40]. Also reaction products with amino acids and oligo- or polypeptides for use in cosmetic formulations are known [43]. Sorbitan esters from ether carboxylates are described as emulsifiers or mild surfactants in cosmetic formulations [39] and alkyl ether carboxylic acid taurides as nonirritant anionic surfactants for cosmetic cleaners in particular [44]. Using unsaturated ether carboxylates it is possible to make viscous formulations based on combinations of unsaturated and saturated ether carboxylates [111]. Highly purified alkyl ether carboxylates based on alcohol ethoxylates with low free alcohol content have also been described [112]. 

Low-foaming liquid or powdered machine detergents are described using a surfactant system prepared from naturally based raw materials with good biodegradability and detergent properties [135]. These formulations are based on 5-30% alkylpolyglucoside, 5-30% alkyl ether carboxylate, 5-35% soap, and 0-3% of another surfactant. 

The use of alkyl ether carboxylates in manual dishwashing agents was described in 1966 [136]. Subsequently several patents mention combinations of alkyl ether carboxylates with aminoxides [137,142], betaines [138,139,142], different anionic surfactants [140], quaternary compounds [141], alkylpolyglucoside [142], and polyhydroxy fatty acid amide [143]. In all cases the ether carboxylates are used to improve mildness and to achieve good cleaning and lathering properties. 

In 1991 the use of amidether carboxylate in combination with anionics like alkanesulfonate, alkylbenzolsulfonate, and alkyl ether sulfate to improve mildness and foam properties in the presence of soil was described [72]. Later a comparison study of the use of alkyl ether carboxylate, amidether carboxylate, and cocamidopropylbetaine in concentrated dishwashing formulations showed, in addition to the above-mentioned properties, the advantage of ether carboxylates in the construction of highly active formulations [144]. 

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