Interpretation:
The manner of ring closure-conrotatory or disrotatory- for both thermal and photochemical cyclization of (2E,4Z,6Z,8E)-2,4,6,8-decatetraene in to 7,8-dimethyl-1,3,5-cyclooctatriene indicating the stereochemistry is to be stated.
Concept introduction:
An electrocyclic reaction involves the cyclization of a conjugated acyclic system. These reactions are reversible and are highly stereospecific.
In elecrocyclic reactions involving even number of electron pairs, a thermal reaction occurs in conrotatory manner and a photochemical reaction occurs in disrotatory manner.
In elecrocyclic reactions involving odd number of electron pairs, a thermal reaction occurs in disrotatory manner and a photochemical reaction occurs in conrotatory manner.
To predict:
The manner of ring closure-conrotatory or disrotatory- for both thermal and photochemical cyclization of (2E,4Z,6Z,8E)-2,4,6,8-decatetraene in to 7,8-dimethyl-1,3,5-cyclooctatriene.
The stereochemistry of the product.
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Chapter 30 Solutions
Organic Chemistry
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