Acid chloride reaction summary

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]. 

The most important reactions of carboxylic acids are the conversions to various carboxylic acid derivatives, e.g. acid chlorides, acid anhydrides and esters. Esters are prepared by the reaction of carboxylic acids and alcohols. The reaction is acid catalysed and is known as Fischer esterification (see Section 5.5.5). Acid chlorides are obtained from carboxylic acids by the treatment of thionyl chloride (SOCI2) or oxalyl chloride [(COCl)2], and acid anhydrides are produced from two carboxylic acids. A summary of the conversion of carboxylic acid is presented here. All these conversions involve nucleophilic acyl substitutions (see Section 5.5.5). 

So what is new here We can save time, materials and effort if we combine two reactions in one operation. These tandem processes, as they are called, avoid the isolation of potentially difficult intermediates and may avoid the need for control over reactions in chapter 19 we discussed the need for control in the acylation of enolates. Workers at Merck1 combined the difficult acylation of enolates 7 by acid chlorides with the capture of the intermediates 9 by hydrazine to give stable pyrroles 10. This is a summary of their method ... 

Summary TNT can be made by reacting a 99% nitric acid/methylene chloride mixture with toluene in the presence of 98% sulfuric acid. The 99% nitric acid/methylene chloride mixture is prepared by extracting a mixture of potassium nitrate or sodium nitrate and sulfuric acid. The reaction mixture is then treated with water, and then filtered to collect any precipitated TNT. The upper methylene chloride layer is then decanted, and evaporated to yield dry solid of TNT. The TNT is then purified by mixing it with 70% sulfuric acid. The acidic mixture is then filtered to collect the TNT, which is then washed with water, and then dried. 

Summary of Reaction of Acid Chlorides, Anhydrides, Esters, and Amides with Water... 

In summary, reactions of nitronates with acid anhydrides or acyl chlorides give the O-acylated products, and reactions with acyl imidazoles, phenyl esters, acyl nitriles, and enol-lactones gives the C-acylated products, (see Eq. 5.13).25 The C/O selectivity of nitronate acylation by RCOX is qualitatively correlated with strength (pKJ of the acid HX conjugated to the leaving group X .25... 

A summary of the results of the experiments on the cyclization of 7-2-phenanthrylbutyric acid may be found in Table XIV. The sharp contrast between the direction of ring closure with hydrogen fluoride (item 6) and with stannic chloride in the Friedel-Crafts-reaction (item 1) is quite striking and of obvious practical significance. Some further indications that hydrogen fluoride has an unusual influence on the ori-... 

Summary Anhydrous ammonia can be prepared by treating an ammonium salt with a warm solution of sodium hydroxide, or potassium hydroxide. In the following procedure, the ammonium salt is either ammonium chloride or ammonium sulfate, which are first prepared by reaction of household ammonia with the corresponding acid. Thereafter, the resulting ammonium salt is then treated with sodium hydroxide, or potassium hydroxide to yield ammonia gas, which is then dried to yield the anhydrous gas. 

Summary Anhydrous hydrogen chloride is readily prepared by reacting concentrated sulfuric acid with pickling salt. During the reaction, hydrogen chloride gas is steadily evolved. 

Some economy can be gained in the chlorine cycle by using method 7 for preparing the methyl chloride from by-product hydrochloric acid coming out of the process. This could be accomplished by a catalyzed reaction of the concentrated acid with methanol2 and would eliminate half of the requirement of free chlorine given in equation 11. The rest of the free chlorine still is necessary for reaction with the silicon, however. The amended summary of the process then becomes... 

Summary TNT can be made by treating toluene with 99% nitric acid in methylene chloride. After the reaction, the TNT is then recovered by reciystallization. The reciystallized TNT is collected by filtration, washed, dried, and then purified with 70% sulfuric acid. 

Summary PVN is conveniently prepared by reacting polyvinyl alcohol (PVA) with 99% nitric acid in the presence of acetic anhydride in methylene chloride. The reaction is mild, and is kept at a temperature below 0 Celsius at all times to avoid decomposition of the polyvinyl alcohol. After the initial reaction, the reaction mixture is refluxed for a short period of time, and then evaporated to remove the solvent. Thereafter, the PVN product is collected by drowning the reaming reaction mixture into ice-cold water, followed by filtration, washing, and then drying. 

Summary DINA is prepared by reacting diethanolamine with hydrochloric acid, and nitric acid in methylene chloride. After the reaction, the mixture is washed with water, sodium bicarbonate solution, and then evaporated to dry residue. The dry residue is then dissolved in methylene chloride, and then passed through a column filled with silicon dioxide, which absorbs impurities. Afterwards, the filtered mixture is evaporated by distillation to yield dry product. Commercial Industrial note ... 

Summary DINA is prepared by reacting diethanolamine with 99% nitric acid in the presence of acetyl chloride and acetic anhydride. In the first phase of the preparation, the nitric acid is mixed with diethanolamine, and allowed to stand overnight. Thereafter, the acid mixture is treated with acetyl chloride and acetic anhydride. The reaction mixture is then drowned into water the product is then filtered, dissolved in acetone, and then precipitated again by the addition of water. The pure DINA is then filtered-off, washed, and dried. Commercial Industrial note For related, or similar information, see Application No. 478,437, March 24, 1983, by Hercules Incorporated, to Ronald L. Simmons, Destin, FL, and Herbert L. Young, Shalimar, FL. Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

Summary 4,4-DNB is prepared by reducing TNB with potassium iodide in the presence of methanol. The reaction is quite slow, taking about 6 days, and after the reaction period, the mixture is acidified with concentrated hydrochloric acid to convert the potassium salt of 4,4-DNB into the free 4,4-DNB. The product isthen extracted into methylene chloride, and then evaporated. Commercial Industrial note For related, or similar information, see Application No. 082,879, February 13th,... 

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