Show how you might use olefin metathesis to assemble the following alkenes from smaller units:


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Verified step by step guidance

1. Identify the target alkenes in the problem and recognize that olefin metathesis is a reaction that involves the redistribution of alkene fragments.
2. For each target alkene, determine the smaller alkene units that could be combined through olefin metathesis to form the desired product.
3. Consider the use of a catalyst, such as Grubbs' catalyst, which is commonly used to facilitate olefin metathesis reactions.
4. Propose a retrosynthetic analysis for each target alkene, breaking it down into smaller alkene units that can undergo metathesis.
5. Outline the forward synthesis, showing how the smaller alkene units can be combined using olefin metathesis to form the target alkenes.

Key Concepts

Olefin Metathesis

Olefin metathesis is a chemical reaction that involves the exchange of alkene fragments to form new alkenes. This process is facilitated by catalysts, typically based on transition metals, which enable the breaking and reforming of carbon-carbon double bonds. It is a powerful tool in organic synthesis, allowing for the construction of complex molecules from simpler ones.

Catalysts in Metathesis

Catalysts play a crucial role in olefin metathesis by lowering the activation energy required for the reaction to occur. Common catalysts include Grubbs and Schrock catalysts, which are designed to stabilize the transition states of the reaction. Understanding the choice of catalyst is essential for optimizing reaction conditions and achieving desired selectivity in product formation.

Alkene Synthesis

Alkene synthesis refers to the methods used to create alkenes, which are hydrocarbons containing at least one carbon-carbon double bond. In the context of olefin metathesis, smaller alkene units can be combined to form larger, more complex alkenes. Recognizing the structural features of the target alkenes is vital for planning the metathesis reaction and selecting appropriate starting materials.