What will be formed by deprotonation of terminal alkyne?

If you treat a “terminal alkyne” (an alkyne that ends in a C-H bond) with a strong base such as NaNH2, it will be deprotonated to form its conjugate base – called an “acetylide”.

What is the theoretical explanation for the acidic character of terminal alkynes?

The acidity of a terminal alkyne is due to the high level of s character in the sp hybrid orbital, which bonds with the s orbital of the hydrogen atom to form a single covalent bond. The high level of s character in an sp‐hybridized carbon causes the overlap region of the σ bond to shift much closer to the carbon atom.

Can Nah deprotonate terminal alkyne?

To deprotonate terminal alkynes, sodium hydroxide will not work. Instead, you should use sodium amide (NaNH2).

Which base can completely deprotonate a terminal alkyne?

Alkynes have pKa values of about 25, so that a good (strong, that is) base that can deprotonate them is Sodium amide , NaNH₂. Indeed, sodium amide does deprotonate terminal alkynes (it can be used for elimination reactions, too).

How is a terminal alkyne deprotonated in a hydrocarbon?

Summary Terminal alkynes are unusual for simple hydrocarbons in that they can be deprotonated (pKa= 26) using an appropriate base (typically NaNH2, pKa = 36) to generate a carbanion.

What is the acidity of a terminal alkyne?

Acidity of Terminal Alkynes Summary. Terminal alkynes are unusual for simple hydrocarbons in that they can be deprotonated (pKa = 26) using an appropriate base (typically NaNH2, pKa = 36) to generate a carbanion (i.e. a carbon atom bearing a negative charge). This carbanion can be used as a C centered nucleophile.

Can a terminal alkyne be converted to a carbanion?

Summary. Terminal alkynes are unusual for simple hydrocarbons in that they can be deprotonated (pK a = 26) using an appropriate base (typically NaNH 2, pKa = 36) to generate a carbanion. The acetylide carbanion is a good C nucleophile and can undergo nucleophilic substitution reactions…

How are terminal alkynes used as nucleophiles?

Terminal alkynes are unusual for simple hydrocarbons in that they can be deprotonated (pK a = 26) using an appropriate base (typically NaNH 2, pKa = 36) to generate a carbanion ( i.e. a carbon atom bearing a negative charge). This carbanion can be used as a C centered nucleophile.