Bis acids

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. 

In an interesting variation on this theme, the bis acid chloride of diethylmalonate (138) is condensed with the 0-methyl ether of urea to afford the imino ether of the barbituric acid (139). Heating this ether at 200°C results in 0 to N migration of the methyl group and formation of metharbital (140). ... 

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]. 

Polyimides syntheses starting from dianhydrides (or derivatives such as bis acid-esters) and diamines (or derivatives like silyl- substituted diamine or isocyanate)... 

The template in this case not only acts as directing agent but also is a component of the final assembly. By reacting covalently with the bis(acid chloride), the... 

A similar approach was employed by Leigh [54] to prepare catenane 15 in one step by reacting bis(acid chloride) 11 with bis-amine 16 under high dilution conditions (see Scheme 10). 

Scheme 22 Cross-coupling reaction of Ar3Bi with bis-acid chlorides...

Examples where the phenolic hydroxy groups were utilized include the preparation of lignin epoxies by reaction with epichlorohydrin (2), esterifications with bis-acid chlorides (3) and cyanuric chloride (4), and polymerization with aziridines (5). 

By appending crown ether moieties to the amidopyrrole skeleton it had been shown that it is possible to both enhance the binding of anions to the cleft by the introduction of caesium cations but only with a limited degree of success (Figure 16).13 Compounds 16 and 17 were synthesized by reaction of the 4 -aminobenzo-15-crown-5 with the 2-methyl-5-mono-acid chloride-3,4-diphenylpyrrole and the analogous 2,5-bis-acid chloride in 28 and 33% respective yields. 

The bis acid from step 6 (1.35 g) and sodium bicarbonate (0.661 g) in water (150 ml) were warmed and stirred until a clear solution was obtained. This solution was filtered and the filtrate was freeze dried to give 1.43 g of the required disodium salt. 

Miller and Neenan 3 reported the preparation (Scheme 5.22) of a polyamido cascade 82. The bis(acid halide) (83) of 5-nitroisophthalic acid was treated with aniline to gene-... 

Pentaerythritol phosphate has an excellent char-forming ability owing to the presence of the pentaerythritol structure. The bis-melamine salt of the bis acid phosphate of pentaerythritol is also available commercially. This is a high melting solid that acts as an intumescent flame-retardant additive for polyolefins. Synergistic combinations with ammonium polyphosphates have also been developed primarily for urethane elastomers. Self-condensation of tris(2-chloroethyl) phosphate produces oligomeric 2-chloroethylphosphate. It has a low volatility, and is useful in resin-impregnated air filters, in flexible urethane foams and in other structural foams.11... 

Diphenylphosphoryl azide (DPPA) 58 was first introduced as a reagent for peptide synthesis by Yamada in 197233 and has been widely used since it gives good yields and very little racemization. It may also be used to bring about a modified Curtius reaction in which a carboxylic acid, R CC H and an alcohol, R2OH, react in the presence of triethylamine to afford the carbamate R1 NHCO2R2.33 In Protocol 15, the use of DPPA to form a macrocyclic lactam 61 is illustrated. The 82% yield of the product using this method should be compared with the value of 24% for reaction of the bis(acid chloride) of 59 with the diamine 60. 

The secondary amino groups of low molecular hemiporjrfiyrazine [from 1,2-dicy-anobenzene and (104 a) react with bis-(acid chlorides) in dimethylacetaminde/triethyl-amine at low temperature to polyamidohexaazacyclanes (112). In (112) the center is blocked against metal introduction ... 

This system was prepared in 23% yield via the condensation reaction between the bis(acid chloride) form of sapphyrin 5.110 and bis(aminopropyl)diaza-18-crown-6 (5.128) (Scheme 5.6.5). It was hoped that this crown sapphyrin system might function as a ditopic ligand, capable of coordinating simultaneously both cationic and anionic substrates. To date, some preliminary evidence in favor of this proposal has been obtained. For instance, in work involving NH4F as the substrate, it was found that NH4" and F are simultaneously bound by the crown sapphyrin receptor. However, at present the structural nature of this proposed interaction remains indeterminate. 

Dimeric sapphyrins 5.138 and 5.139, containing chiral bridging units have also been synthesized. These were obtained by treating the activated form of the sapphyrin mono-acid 5.109 with a chiral diamine (i.e., 5.135 or 5.136 Figure 5.6.3). This afforded the corresponding sapphyrin dimers 5.138 and 5.139 in yields as high as 60% (Schemes 5.6.8 and 5.6.9). The cyclic sapphyrin dimer 5.140 was also prepared from the chiral diamine 5.137 and bis-acid sapphyrin 5.109. However, in this latter instance a stepwise synthetic approach was required. It involved reacting two equiva-... 

Polycondensates 27 and 28 (Fig. 9-22), incorporating either the 1,3- or 1,1 -disubstituted ferrocene unit, were prepared by solution polymerisation. Polymers 27 [25] were obtained by reaction of the novel monomer 29 [25] (Fig. 9-23) with the desired bis(acid chloride) 31 (Fig. 9-23) in refluxing CH2CI2 in the presence of triethylamine. Polymers 28 [25] were prepared following the same procedure from bis-phenol 30 [16] (Fig. 9-23). 

Weakly perturbed bi-acid molecules (H02C-(CH0H)2-C02H) 2... 

Scheme 8.27 Soluble oligomeric bis acid chloride (OBAC).

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