How would you synthesize (E) - and (Z) -3-heptene from acetylene and any other chemicals?

Name: Problem 51, Chapter 27: General Chemistry: Principles and Modern Applications
Uploaded: 2021-03-09T17:40:22-08:00
Duration: 4 min 16 s
Channel: Nicholas Sacco
Description: How would you synthesize (E) - and (Z) -3-heptene from acetylene and any other chemicals?

step 1 We're asked to create E and Z -3 heptene from Cetylene. So C -edaline is an alkyn. In order to g

How would you synthesize (E) - and (Z) -3-heptene from...

Key Concepts

Partial Hydrogenation of Alkynes

Partial hydrogenation is a technique used to selectively reduce an alkyne to an alkene without further saturation to an alkane. By choosing specific catalysts and conditions—such as using a poisoned catalyst like Lindlar’s catalyst for cis (Z) alkenes or alternative methods for trans (E) alkenes—chemists can control the stereochemical outcome of the reduction process.

Stereoselective Synthesis

Stereoselective synthesis involves designing reaction conditions and selecting reagents that favor the formation of a specific stereoisomer over another. When transforming an alkyne intermediate into an alkene, the selection of the proper reduction method is crucial to obtaining either the (E)- or (Z)-isomer with high selectivity.

Acetylene Reactivity

Acetylene is the simplest alkyne and features acidic terminal hydrogens, which under basic conditions can be deprotonated to form acetylide ions. These nucleophilic species are instrumental in carbon–carbon bond forming reactions, allowing for the construction of larger and more complex carbon frameworks.

Carbon–Carbon Coupling Reactions

Carbon–carbon coupling reactions are key methods in organic synthesis that enable the formation of new bonds between carbon atoms. In the context of synthesizing higher alkenes, an acetylide ion derived from acetylene can react with an appropriate alkyl halide or other electrophile to extend the carbon chain, establishing the desired carbon skeleton.