Alkynes as acids

A reaction of immense industrial importance is the formation of oxacy-clopropane itself (most often called ethylene oxide) by oxidation of ethene with oxygen over a silver oxide catalyst at 300°  

Propene and higher alkenes are not efficiently epoxidized by oxygen and Ag20 in the same way as ethene is because of competing attack at other than the double-bond carbons. 

A characteristic and synthetically important reaction of ethyne and 1-alkynes is salt ( acetylide ) formation with very strong bases. In such reactions the alkynes behave as acids in the sense that they give up protons to suitably strong bases  

Water is too weak a base to accept protons from alkynes consequently no measurable concentration of H30 is expected from the ionization of alkynes in dilute aqueous solutions. Therefore we have no quantitative measure of 1-alkyne acidity in aqueous solution other than that it probably is about 1010 times less acidic than water, as judged from measurements in other solvents to be discussed shortly. In the gas phase, however, the situation is reversed, and ethyne is a stronger acid than water  

11 Alkenes and Alkynes II. Oxidation and Reduction Reactions. Acidity of Alkynes 

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