Anhydride

I saw a chest full of mixed potassic chlorate and black oxide of manganese, with an apparatus for heating it, and producing oxygen -- a foolish thing, for additional oxygen could not alter the quantity of breathed carbonic anhydride, which is a direct narcotic poison. ❋ Unknown (1906)

~ To understand the reaction which occurs, it must be remembered that a volatile acid anhydride is expelled from its salts when heated with an anhydride which is not volatile. ❋ William McPherson (N/A)

Alar is manufactured by mixing succinic anhydride with 1,1,dimethylhydrazine UDMH, a toxic component of rocket fuel. ❋ Wendy Gordon (2011)

My most ambitious attempt was a multistep sequence aimed at synthesizing aspirin, for which I needed acetic anhydride, which had to be made from acetyl chloride, for which I needed phosphorus trichloride, for which I needed to burn red phosphorus in a stream of chlorine gas. ❋ Unknown (2009)

"The significant current increase in demand for maleic anhydride and projected long-term global customer requirements necessitated the expansion and will strengthen our advantage as leading producer of this important chemical in Europe," said Sasol-Huntsman managing director ❋ Unknown (2008)

The segment -- which serves customers in the chemical, paint and adhesives industries -- produces and supplies acetyl products such as acetic acid, vinyl acetate monomer, acetic anhydride and other acetyl derivatives. ❋ Unknown (2007)

To the suspension is then added slowly a solution of about two equivalents of trifluoroacetic anhydride dissolved in acetonitrile and previously cooled to about -20 degrees C. ❋ Unknown (2006)

The most acid rain recorded was in Glasgow, Scotland; the reported value (representing an average of several individual samples) was 109.16 grains of sulfuric anhydride per gallon of rainwater. ❋ Unknown (2006)

Preferably a slight excess over the five mols is employed to insure complete utilization of the mixed anhydride. ❋ Unknown (2006)

Two gallons of trifluoroacetic anhydride are required per mol. of lysergic acid for the rapid and complete conversion of the lysergic acid into the mixed anhydride. ❋ Unknown (2006)

When sulfuric anhydride (SO3) is dissolved in water, each mole of SO3 becomes a mole of sulfuric acid, H2SO4. ❋ Unknown (2006)

A solution of the mixed anhydride of lysergic acid and trifluoroacetic acid is prepared from 2.68 g. of d-lysergic acid and 4.4 g. of trifluoroacetic acid anhydride in 100 ml. of acetonitrile by the method of Example One. ❋ Unknown (2006)

The conversion of the mixed anhydride into an amide by reacting the anhydride with the nitrogenous base, such as an amino compound, can be carried out at room temperature or below. ❋ Unknown (2006)

By my invention I have provided a simple and convenient method of preparing lysergic acid amides, which comprises reacting lysergic acid with trifluoroacetic anhydride to produce a mixed anhydride of lysergic and trifluoroacetic acids, and when reacting the mixed anhydride with a nitrogenous base having at least one hydrogen linked to nitrogen. ❋ Unknown (2006)

The mixed anhydride of lysergic and trifluoroacetic acids is relatively unstable, especially at room temperature and above, and must be stored at a low temperature. ❋ Unknown (2006)

The reaction of the lysergic and the trifluoroacetic anhydride is a low temperature reaction, that is, it must be carried out at a temperature below about 0 degrees C. ❋ Unknown (2006)

The mixed anhydride can be separated in the form of an oil by evaporating the solvent in vacuo at a temperature below about 0 degrees centigrade. ❋ Unknown (2006)

The mixed anhydride itself, since it contains a lysergic acid group, also can exist in the reaction mixture in large part as an ionic adduct with trifluoroacetic anhydride or trifluoroacetic acid. ❋ Unknown (2006)