|| Chapter 9 : Alkynes
Preparation of Alkynes via Elimination reactions
Reaction Type: Elimination (E2)
- The two p bonds of an alkyne can be formed using two consecutive elimination
- The leaving groups are usually halides (esp. Br
- Reagent : usually NaNH2 (a strong base, pKa
- Either geminal (1,1-) or vicinal (1,2-) dihalides can
- Since 1,2-dihalides can be prepared by addition
of X2 to an alkene, an alkene can be converted into an alkyne
in two steps.
- These reactions are typically E2
reactions and occur via an alkenyl halide.
- The strong base is needed in order to cause elimination
of the alkenyl halide.
|What is the alkyne product from the reactions
of the following with NaNH2: