Acetic-phosphoric anhydride

Alcohols can also be acylated by mixed organic-inorganic anhydrides, such as acetic-phosphoric anhydride, MeCOOPO(OH)2 (see 10-35). ... 

Acetic-phosphoric anhydride, ho-p-o cch. [1, 4, before Aceloacetyl fluoride],... 

Thiele reaction Acetic anhydride. Acetic phosphoric anhydride. Boron trifluoride etherate. 

FIGURE 3.10 (a) Electrostatic repnlsion between adjacent partial positive charges (on carbon and phosphorns, respectively) is relieved upon hydrolysis of the anhydride bonds of acetic anhydride and phosphoric anhydrides. The predominant form of pyrophosphate at pH values between 6.7 and 9.4 is shown, (b) The competing resonances of acetic anhydride and the simnltaneons resonance forms of the hydrolysis product, acetate. 

Resonance stabilization in the products is best illustrated by the reactant anhydrides (Figure 3.10b). The unpaired electrons of the bridging oxygen atoms in acetic anhydride (and phosphoric anhydride) cannot participate in resonance structures with both electrophilic centers at once. This competing resonance situation is relieved in the product acetate or phosphate molecules. 

The reaction of condensed phosphoric acid with castor oil gave a poly-phosphoric acid ester, which after neutralization with ammonia shows a high wetting power [32]. Glycerol trioleate was reacted with octametaphosphoric acid at 40°C in the presence of acetic acid anhydride. The reaction product was neutralized with triethanolamine [32,33]. 

When the reaction is completed, add 20 ml of glacial acetic acid and rapidly transfer the reaction mixture onto a filter No. 2 for filtration in an inert atmosphere (see Fig. 64b). Separate the nitrosyl-sulphuric acid crystals in an atmosphere of dry nitrogen, wash them on a filter with glacial acetic acid cooled to 5 °C, rapidly transfer them to a preliminarily weighed watch glass and put them in a vacuum desiccator over phosphoric anhydride. Dry them for two or three hours. Write the equation of the reaction. Weigh the dry crystals and calculate the yield in per cent. 

A fresh solution of 1 mole-equivalent of p-fluorobenzylamine and 1 mole equivalent methylamine is added to a solution of 1 mole-equivalent 7-oxo-8-methylnonanoic acid in 20 ml ethanol. The mixture is warmed at 40°C for a night. 0.1 g of platinum oxide is then added and the mixture is hydrogenated under ordinary pressure at 40°C. After the theoretical amount of hydrogen has been absorbed, the catalyst is filtered off and the solvent is evaporated under reduced pressure. The oily residue crystallized quickly, at room temperature. The product is purified by recrystallizing it from ethyl acetate and is dried over phosphoric anhydride in a closed vessel. (+/-)-7-((p-Fluorobenzyl)amino)-8-methylnonanoic acid is a crystalline solid MP 88°-89°C. 

Regenerated (R-) cellulose was obtained by hydrolyzing the Ac-cellulose with sodium hydroxide-acetone aqueous solution (15). According to the Alexander and Michell s report (16), the degree of polymerization of R-cellulose was determined viscometrically, after it was nitrated with the mixture of phosphoric anhydride and fumic nitric acid then dissolved in ethyl acetate. 

So why ATP First, we want a compound with intermediate hydrolysis energy so it can pick up energy from some reactions and deliver to others. Second we want a kinetically stable molecule which is thermodynamically unstable. Thus acetic acid anhydride would not work it is thermodynamically unstable to hydrolysis, but it is also kinetically unstable, with the carbonyl carbons wide open to water attack. Phosphoric acid anhydride is equally unstable, but is is sterically protected from water attack - in order to react quickly we need a catalyst -perfect. 

Nitration. As pointed out in Vol. II (p. 321) the only industrial method ol nitrating cellulose consists in using a nitric acid -sulphuric acid nitrating mixture. The other nitrating mixtures, such as nitric acid/phosphoric anhydride, nitric acid/acctic anhydride, nitric acid/chlorinated hydrocarbons were in use occasionally on a laboratory scale to solve some problems connected with the nitration of cellulose. Thus Bennett and Timell (10 confirmed the work of Bouchonnet, Trombe and Petitpas (Vol. II, p. 344) that the nitration of cotton dust with a mixture of nitric acid-acetic acid acelic anhydride (in proportion 43 32 25) at 0 C can yield fully nitrated cellulose, that is, cellulose trinitrate of 14.14% N... 

Since, as has just been done, the acid-amide may be made by dehydrating the ammonium salt of an acid, thus, in a single operation the nitrile may be obtained directly from the ammonium salt, if it is treated with a powerful dehydrating agent, e.g. ammonium acetate heated with phosphoric anhydride ... 

Masamune, in his studies of lactonization methodology, had previously converted 18 into cytochalasin B (20) as follows. The carboxylic acid moiety was converted to the thioester via the intermediate phosphoric anhydride. Exchange of the THP ethers for acetate groups then led to lactonization precursor... 

Despite wide variations of synthesis conditions, the treatment of cellulose with dimethylphosphite, monomethylphosphite and phosphorous acid failed to yield phosphites containing only one type of phosphorus-containing groups. This difficulty was overcome by using phosphoric anhydrides as the esterifying reagents. The action of mixed anhydrides of phosphorous acids and acetic acid on cellulose has yielded cellulose esters with alkyl-(methyl-)phosphorous acid (73) ... 

Simple derivatives of (a-hydroxyalkyl)phosphonic and analogous acids have been obtained directly by procedures analogous to those adopted for the parent compounds. Thus, O-acetates of (2,2,2-trichloro-l-hydroxyethyl)phosphonic acid esters have been prepared through the interaction of the appropriate halogenated acetaldehyde and phosphorous-acetic acid anhydrides An aromatic aldehyde and dialkyl phospho-roisocyanatidite in the presence of water or an alcohol yields analogous 0-carbamoyl derivatives of (a-hydroxybenzyl)phosphonic diesters, probably through cyclic intermedi-ates ". ... 

For example, EtCl reacts with the alloy to give tetraethyllead in 85 % yield [9]. This method is such that only one quarter of the lead is converted to lead alkyl and the remainder has to be recycled. Unfortunately, sodium-rich alloys such as Na4Pb do not react satisfactorily. Ketones, aldehydes, acetals, acid anhydrides, esters, amides, phosphoric acid esters, organosilicons, organoaluminum compounds, etc. as reaction accelerators of the alloy process have been reported [9]. For example, the reaction of EtCl at 100-120 °C in the presence of 0.1 % acetone gives tetraethyllead in 98% yield [10]. 

B3 the slow distillation of an aromatic carboxylic acid and acetic anhydride in the presence of a little phosphoric acid ... 

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