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Dicarboxylic chlorides

Coupling of living anionic polymerization and living ROMP may be achieved by terminating living anionic polymer chains with norborn-2-ene-5-carboxylic chlo-ride425 or norbomene-2,3-dicarboxylic chloride. 6 427 This end-functionalized polymer may then be polymerized via ROMP (Scheme 47). [Pg.158]

Wang and Zhang used enantiopure cyclohexane-1,2-dicarboxylic chloride for the construction of the diacyl backbone [66]. Variation was observed through different diastereomers and aryl substituents. In the AHF of vinyl acetates and allyl amides, the all- R) diastereomer with 2-Cl-phenyl groups produced the best results. In the corresponding Rh(acac)(P-P) complex, a bite angle of 84.9° was calculated. [Pg.223]

Decane-1 10-dicarboxylic acid from sebacic acid. Convert sebacic acid into the acid chloride by treatment with phosphorus penta-chloride (2 mols) and purify by distillation b.p. 146-143°/2 mm. the yield is almost quantitative. Dissolve the resulting sebacoyl chloride in anhydrous ether and add the solution slowly to an ethereal solution of excess of diazomethane (prepared from 50 g. of nitrosomethylurea) allow the mixture to stand overnight. Remove the ether and excess of diazomethane under reduced pressure the residual crystalline 1 8-bis-diazoacetyloctane weighs 19 -3 g. and melts at 91° after crystaUisation from benzene. [Pg.905]

The benzoic acid derivative 457 is formed by the carbonylation of iodoben-zene in aqueous DMF (1 1) without using a phosphine ligand at room temperature and 1 atm[311]. As optimum conditions for the technical synthesis of the anthranilic acid derivative 458, it has been found that A-acetyl protection, which has a chelating effect, is important[312]. Phase-transfer catalysis is combined with the Pd-catalyzed carbonylation of halides[3l3]. Carbonylation of 1,1-dibromoalkenes in the presence of a phase-transfer catalyst gives the gem-inal dicarboxylic acid 459. Use of a polar solvent is important[314]. Interestingly, addition of trimethylsilyl chloride (2 equiv.) increased yield of the lactone 460 remarkabiy[3l5]. Formate esters as a CO source and NaOR are used for the carbonylation of aryl iodides under a nitrogen atmosphere without using CO[316]. Chlorobenzene coordinated by Cr(CO)j is carbonylated with ethyl formate[3l7]. [Pg.190]

The FCC is to food-additive chemicals what the USP—NF is to dmgs. In fact, many chemicals that are used in dmgs also are food additives (qv) and thus may have monographs in both the USP—NF and in the FCC. Examples of food-additive chemicals are ascorbic acid [50-81-7] (see Vitamins), butylated hydroxytoluene [128-37-0] (BHT) (see Antioxidants), calcium chloride [10043-52-4] (see Calcium compounds), ethyl vanillin [121-32-4] (see Vanillin), ferrous fumarate [7705-12-6] and ferrous sulfate [7720-78-7] (see Iron compounds), niacin [59-67-6] sodium chloride [7647-14-5] sodium hydroxide [1310-73-2] (see lkaliand cm ORiNE products), sodium phosphate dibasic [7558-79-4] (see Phosphoric acids and phosphates), spearmint oil [8008-79-5] (see Oils, essential), tartaric acid [133-37-9] (see Hydroxy dicarboxylic acids), tragacanth [9000-65-1] (see Gums), and vitamin A [11103-57-4]. [Pg.446]

The direct combination of selenium and acetylene provides the most convenient source of selenophene (76JHC1319). Lesser amounts of many other compounds are formed concurrently and include 2- and 3-alkylselenophenes, benzo[6]selenophene and isomeric selenoloselenophenes (76CS(10)159). The commercial availability of thiophene makes comparable reactions of little interest for the obtention of the parent heterocycle in the laboratory. However, the reaction of substituted acetylenes with morpholinyl disulfide is of some synthetic value. The process, which appears to entail the initial formation of thionitroxyl radicals, converts phenylacetylene into a 3 1 mixture of 2,4- and 2,5-diphenylthiophene, methyl propiolate into dimethyl thiophene-2,5-dicarboxylate, and ethyl phenylpropiolate into diethyl 3,4-diphenylthiophene-2,5-dicarboxylate (Scheme 83a) (77TL3413). Dimethyl thiophene-2,4-dicarboxylate is obtained from methyl propiolate by treatment with dimethyl sulfoxide and thionyl chloride (Scheme 83b) (66CB1558). The rhodium carbonyl catalyzed carbonylation of alkynes in alcohols provides 5-alkoxy-2(5//)-furanones (Scheme 83c) (81CL993). The inclusion of ethylene provides 5-ethyl-2(5//)-furanones instead (82NKK242). The nickel acetate catalyzed addition of r-butyl isocyanide to alkynes provides access to 2-aminopyrroles (Scheme 83d) (70S593). [Pg.135]

Substitutedisoxazole-3,5-dicarboxylic acids have been prepared from ethyl nitroacetate and an aldehyde (63BCJii50). A related reaction leads to diethyl 4-hydroxyisoxazole-3,5-dicarboxylate (334) and involves the reaction of acetonedicarboxylic acid ester (333) with nitrosyl chloride (78JHC1519). [Pg.85]

Claisen ester condensation, 6, 279 Thiazolecarboxylic acid chlorides reactions, 6, 279-280 Thiazolecarboxylic acid hydrazides synthesis, 6, 280 Thiazolecarboxylic acids acidity, 6, 279 decarboxylation, 6, 279 reactions, S, 92 6, 274 Thiazole-2-carboxylic acids decarboxylation, S, 92 Thiazole-4-carboxylic acids stability, S, 92 Thiazole-5-carboxylic acids decarboxylation, S, 92 Thiazole-4,5-dicarboxylic acid, 2-amino-diethyl ester reduction, 6, 279 Thiazole-4,5-dicarboxylic acids diethyl ester saponification, 6, 279 Thiazolediones diazo coupling, 5, 59 Thiazoles, 6, 235-331 ab initio calculations, 6, 236 acidity, S, 49 acylation, 6, 256 alkylation, S, 58, 73 6, 253, 256 analytical uses, 6, 328 antifogging agents... [Pg.873]

The first, and still widely used, polymer-supported ester is formed from an amino acid and a chloromethylated copolymer of styrene-divinylbenzene. Originally it was cleaved by basic hydrolysis (2 N NaOH, FtOH, 25°, 1 h). Subsequently, it has been cleaved by hydrogenolysis (H2/Pd-C, DMF, 40°, 60 psi, 24 h, 71% yield), and by HF, which concurrently removes many amine protective groups. Monoesterification of a symmetrical dicarboxylic acid chloride can be effected by reaction with a hydroxymethyl copolymer of styrene-divinylbenzene to give an ester a mono salt of a diacid was converted into a dibenzyl polymer. ... [Pg.260]

Caviion The reaction of phosphorous pentachloride toith diethyl acetone-l,3-dicarboxylate should be carried out in a hood, since hydrogen chloride is evolved. [Pg.63]

Alcoholysis of the acid chloride of a dicarboxylic acid with a polyhydroxy alcohol ... [Pg.695]

When a dilute solution of 6-phenylhexanoyl chloride in carbon disulfide was slowly added (over a period of eight days ) to a suspension of aluminum chloride in the same solvent, it yielded a product A (C12H14O) in 67% yield. Oxidation of A gave benzene-l,2-dicarboxylic acid. [Pg.517]

The dicarboxylic acid chlorides from sebacic and azelaic acid react with 2 moles of enamine to give the tetraketone (117), which on base cleavage... [Pg.138]

Dicarboxylic acid dichlorides with less than seven carbon atoms do not react to give tetraketones similar to 117, but instead undergo an intramolecular acylation (72) to give on hydrolysis the vinylogous acid anhydride (118), e.g., from succinyl chloride and the enamine (113). [Pg.139]

Monoesterification of a symmetrical dicarboxylic acid chloride can be effected by reaction with a hydroxymethyl copolymer of styrene-divinylbenzene to give an ester a mono salt of a diacid was converted into a dibenzyl polymer." ... [Pg.428]

Dicarboxylic acids have been prepared by the stepwise acylation and Wolff-Kishner reduction of thiophene or di-2-thienylmethane with ester chlorides of dicarboxylic acids. Another method consists of the AICI3 catalyzed acylation of w-phenylalkylthiophenes which occurs both in the free thiophenic position and in the para position of the ring (226). Hypochlorite oxidation and desulfurization then give diacides such as (227)... [Pg.111]

Cefpimizole (51) appears to be less active in vitro than cefotaxime and cefoperazone and to have a somewhat narrower activity spectrum although some strains of Pseudomonas are susceptible. It is not orally active, but its performance in vivo appears superior to what would be expected from its in vitro data. Its synthesis begins by acylation of cephaloglycin (48) with the bis acid chloride of imidazole-4,5-dicarboxylic acid (49) to give amide 50. The acetyl moiety at C-3 of this intermediate is displaced with 4-pyridineethanesulfonic acid and sodium iodide to give cef-pimazole (51) [16]. [Pg.185]

A mixture of 4.98 g of acetoacetic acid N-benzyl-N-methylaminoethyl ester, 2.3 g of aminocrotonic acid methyl ester, and 3 g of m-nitrobenzaldehyde was stirred for 6 hours at 100°C in an oil bath. The reaction mixture was subjected to a silica gel column chromatography (diameter 4 cm and height 25 cm) and then eluted with a 20 1 mixture of chloroform and acetone. The effluent containing the subject product was concentrated and checked by thin layer chromatography. The powdery product thus obtained was dissolved in acetone and after adjusting the solution with an ethanol solution saturated with hydrogen chloride to pH 1 -2, the solution was concentrated to provide 2 g of 2,6-dimethyl-4-(3 -nitrophenyl)-1,4-dihydropyridlne-3,5-dicarboxylic acid 3-methylester-5- -(N-benzyl-N-methylamino)ethyl ester hydrochloride. The product thus obtained was then crystallized from an acetone mixture, melting point 136°Cto 140°C (decomposed). [Pg.1070]

Attempts have been made to catalyze the arrangement of 3-oxaquadricyclane to oxepins with transition-metal complexes.1 32 1 35 When dimethyl 2,4-dimethyl-3-oxaquadricyclane-l,5-dicarboxylate is treated with bis(benzonitrile)dichloroplatinum(II) or dicarbonylrhodium chloride dimer, an oxepin with a substitution pattern different from that following thermolysis is obtained as the main product. Instead of dimethyl 2,7-dimethyloxepin-4,5-dicarboxylate, the product of the thermal isomerization, dimethyl 2,5-dimethyloxepin-3,4-dicarboxylate (12), is formed due to the cleavage of a C O bond. This transition metal catalyzed cleavage accounts also for the formation of a 6-hydroxyfulvene [(cyclopentadienylidene)methanol] derivative (10-15%) and a substituted phenol (2-6%) as minor products.135 The proportion of reaction products is dependent on solvent, catalyst, and temperature. [Pg.13]

Oxidation of diethyl 3,6-hexanooxepin-4,5-dicarboxylate with ruthenium(VIII) oxide, generated from ruthenium(III) chloride and sodium periodate in situ, gives the corresponding hexa-no-bridged furan 1 a with loss of two carbon atoms (see Houben-Weyl, Vol. E6a, p 77).200 201 One of the central methylene groups can be replaced by a carbonyl group to give lb.200... [Pg.39]

The synthesis of thiepins 14 was unsuccessful in the case of R1 = i-Pr,79 but if the substituents in the ortho positions to sulfur arc /erf-butyl, then thiepin 14 (R1 = t-Bu R2 = Me) can be isolated in 99% yield.80 Rearrangement of diazo compound 13 (R1 = t-Bu R2 = H), which does not contain the methyl group in position 4, catalyzed by dimeric ( y3-allyl)chloropalladium gives, however, the corresponding e.w-methylene compound. The thiepin 14 (R1 = t-Bu, R2 = H) can be obtained in low yield (13 %) by treatment of the diazo compound with anhydrous hydrogen chloride in diethyl ether at — 20 C.13 In contrast, the ethyl thiepin-3,5-or -4,5-dicarboxylates can be prepared by the palladium catalysis method in satisfying yields.81... [Pg.85]

Similarly, copper(II) 1,8,15,22-tetraazaphthaIocyanine can be made from copper(II) chloride, pyridine-2,3-dicarboxylic acid, and urea in the presence of a catalytic amount of ammonium molybdate(VI), heated to 210DC for 4-5 hours, in a yield of 52%.459... [Pg.829]

Some of the typical conditions of polycondensations used for aliphatic and aromatic monomers are not suitable for furan derivatives, e.g., the melt polycondensation of 2,5-furan dicarboxylic acid chloride with 2,5-b/s(hydroxymethyl) furan at about 80 °C only yields a black insoluble product5. The hydrochloric acid liberated in the reaction is clearly responsible for the charring of the furanic diol which like its simpler homologue furfuryl alcohol, resinifies rapidly in acidic media (see below). [Pg.51]


See other pages where Dicarboxylic chlorides is mentioned: [Pg.250]    [Pg.250]    [Pg.858]    [Pg.181]    [Pg.564]    [Pg.240]    [Pg.66]    [Pg.818]    [Pg.63]    [Pg.307]    [Pg.530]    [Pg.544]    [Pg.37]    [Pg.114]    [Pg.250]    [Pg.293]    [Pg.77]    [Pg.150]    [Pg.39]    [Pg.43]    [Pg.71]   


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A-Dicarboxylic acid halides chlorides

Chemiluminescence of o-Dicarboxylic Acid Chlorides

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Dicarboxylic acid chloride

Dicarboxylic acid chloride anhydrides

Dicarboxylic acid chloride esters

Dicarboxylic acid chloride synthesis

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