(a)
Interpretation: The cyclic product formed on photochemical electrocyclic ring closure of given decatetraene is to be determined.
Concept introduction: Electrocyclic reactions involve ring opening or ring closure in a conjugated polyene. According to Woodward-Hoffmann rules, the acyclic polyene containing even number of bonds in photochemical conditions undergoes reaction in disrotatory fashion and acyclic polyene containing odd number of bonds undergo reaction in conrotatory fashion.
(b)
Interpretation: The cyclic product formed on photochemical electrocyclic ring closure of given decatetraene is to be determined.
Concept introduction: Electrocyclic reactions involve ring opening or ring closure in a conjugated polyene. According to Woodward-Hoffmann rules, the acyclic polyene containing even number of bonds in photochemical conditions undergoes reaction in disrotatory fashion and acyclic polyene containing odd number of bonds undergo reaction in conrotatory fashion.
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Organic Chemistry
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