Acid chlorides structure

Acetamidothiazole and its 4-alkyl derivatives react with chloro-sulfonic acid. The structure of the resulting products was a subject of controversy (172. 393-397). N-acetyl-A -(2-thiazolyl)-sulfamoyl chlorides (189) first proposed were then shown to be 2-acetamido-5-chloro-sulfonylthiazoles (190) (Scheme 120) (367. 368. 398). the latter assignment is based on infrared (368) and chemical evidence (367). 

It should be noted that the host structures were prepared from the simple monoazacrowns by acylating with a bis-acid chloride followed by hydride reduction. 

The structure of this compound is confirmed by the preparation of the 1-acetyl derivative, acid degradation to 4-methylquinoxalin-3-one-2-carboxylic acid (12), and alternative synthesis from the acid chloride of (12) and AW -dimethyluread A most unusual cyclization occurs when AW-dimethyl-o-phenylenediamine (15) is treated with alloxan in ethanolic solution this apparently involves an A-methyl group and leads to the formation of the spirobarbituric acid (16). The struc-... 

Ceftizoxime (83) is structurally of interest in that it lacks any functionality at C-3 and therefore cannot undergo the usual metabolic deacetylation experienced by many cephalosporins. Its synthesis involves condensation of the acid chloride corresponding to ester 74 (74a) with 3-lactam 82. ... 

Ill spectroscopy is a valuable tool for the structural analysis of acid derivatives. Acid chlorides, anhydrides, esters, and amides all show characteristic IR absorptions that can be used to identify these functional groups. 

A sequence of straightforward functional group interconversions leads from 17 back to compound 20 via 18 and 19. In the synthetic direction, a base-induced intramolecular Michael addition reaction could create a new six-membered ring and two stereogenic centers. The transformation of intermediate 20 to 19 would likely be stereoselective substrate structural features inherent in 20 should control the stereochemical course of the intramolecular Michael addition reaction. Retrosynthetic disassembly of 20 by cleavage of the indicated bond provides precursors 21 and 22. In the forward sense, acylation of the nitrogen atom in 22 with the acid chloride 21 could afford amide 20. 

Other substituted systems, however, might be planar due to conjugation effects with acceptor substituents, as has been found in an X-ray structural analysis of 1,4-dioxocin-6-carboxylic acid chloride the eight-membered ring is practically planar with a coplanar arrangement of the substituent.9... 

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... 

The sulfonylated and acylated PPO presents solubility characteristics which are completely different from those of the parent PPO. Table V presents the solubility of some modified structures compared to those of unmodified PPO. It is very important to note that, after sulfonylation, most of the polymers become soluble in dipolar aprotic solvents like dimethyl sulfoxide (DMSO), N,N— dimethylformamide (DMF) and N,N-dimethylacetamide (DMAC). At the same time it is interesting to mention that, while PPO crystallizes from methylene chloride solution, all the sulfonylated polymers do not crystallize and form indefinitely stable solutions in methylene chloride. Only some of the acetylated polymers become soluble in DMF and DMAC, and none are soluble in DMSO. The polymers acetylated with aliphatic acid chlorides such as propionyl chloride are also soluble in acetone. 

The same nonpolar conformation can be achieved by conversion to bicyclic structures. 1,4-Cyclo-addition of ethylene to anthracene-9-carboxylic acid gives acid 68. Successive conversion to the N-methylamide, via the acid chloride, followed by reduction with lithium aluminum hydride produced... 

Those polyester FBAs containing a benzoxazole group are usually prepared from the appropriate o-aminophenol and carboxylic acid (11.45 Y = OH) or one of its derivatives, as shown in Scheme 11.10. The reaction proceeds via an intermediate amide and it can be advantageous to start from an acid derivative such as the acid chloride (11.45 Y = Cl) or ester (11.45 Y = OEt), which are both more effective acylating agents. The preparation of compound 11.36, shown in Scheme 11.11, illustrates this process, but the optimum conditions for ring closure vary considerably from one structure to another. The article by Gold contains a valuable and detailed summary [4]. 

Attachment of carbonyl groups to crowns makes these products more akin structurally to the natural ionophore antibiotics such as valinomycin. The dioxo-derivative (179) of 18-crown-6 was prepared in 35% yield by condensation of tetraethylene glycol and diglycolic acid chloride in benzene at 50 °C for 48 hours (Izatt et al., 1977a and 1977b). This product gives binding constants for Na+, K+ and Ba2+ in methanol which are 102—104 times less stable than for the parent crown - the lower constants are a reflection of less favourable AH values for complexation in these... 

Yoshino reports a novel and general method for the C-3 acylation of indoles with acyl chlorides in the presence of dialkylaluminium chloride which obviates the need for prior N-protection . Interestingly, as described in this preliminary communication, the unprotected indoles 147 are first treated with the Lewis acids prior to addition of the acid chlorides, yielding the desired 3-acyl derivatives 148. In reactions more typical of indoles under acidic conditions, Nakatsuka determined the structures of the dimers and trimers of 1-trimethylacetylindole produced in the presence of aluminium chloride . 

FIGURE 4.62 Oxidative dehalogenation of halothane to form areactive acid chloride intermediate and structures of other anesthetics that can form similar reactive metabolites. 

Type 2 (see p. 370) is obtained by coupling diazotized aminobenzoic acid onto acetoacetarylide. The resulting acid is converted into the acid chloride and condensed with an aromatic diamine (see structure in the appendix). 

The compounds are obtained by coupling diazotized 1-aminoanthraquinone onto 2-hydroxy-3-naphthoic acid, followed by separation, drying, and conversion into the azo dye acid chloride. Condensation with amines (structure 81) is achieved in an aprotic organic solvent. 

Doubling the quinophthalone structure may also be achieved through condensation of two equivalents of 3-hydroxy-quinophthalone carboxylic acid chloride with aromatic diamines [7], The reaction affords orange pigments (140). The acid chloride is prepared from 3-hydroxyquinaldine-4-carboxylic acid and benzene-1,2,4-tricarboxylic acid. 

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