Reduction of Alkynes | Catalytic, Lindlar’s, Dissolving Metal | 9.4 Organic Chemistry

In this lesson Chad covers the the three common reduction reactions for alkynes.

Catalytic Hydrogenation of Alkynes
He begins with a review of the catalytic hydrogenation of alkenes to form alkanes and then shows the analogous catalytic hydrogenation of alkynes to form alkanes also using H2 and an appropriate metal catalyst (Pt, Pd, or Ni).

Alkyne Reduction with Lindlar’s Catalyst
Chad proceeds to show that by using a poisoned catalyst such as Lindlar’s catalyst (Pd with BaSO4 and quinoline), catalytic hydrogenation of an alkyne results in a cis-alkene.

Dissolving Meta Reduction
Finally, Chad shows how dissolving metal reduction (Na / NH3) can be used to reduce an alkyne to a trans-alkene. He includes the dissolving metal reduction mechanism and shows why this mechanism results in a trans-alkene.

If you want all my study guides, quizzes, and practice exams, check out my premium course at https://www.chadsprep.com/organic-chemistry-youtube

00:00 Lesson Introduction
00:36 Review of Catalytic Hydrogenation of Alkenes
01:42 Catalytic Hydrogenation of Alkynes
02:14 Catalytic Hydrogenation of Alkynes with Lindlar’s Catalyst
04:31 Dissolving Metal Reduction of Alkynes (Na / NH3)
05:47 The Dissolving Metal Reduction Mechanism

https://www.chadsprep.com/ #organicchemistry #organicchemistrytutorial #alkynes