A reacting diene must be conjugated and able to adopt the s-cis arrangement. From left to right, furan and cyclopentadiene qualify. The third diene is constrained s-trans and the fused-ring fifth diene also cannot give the required s-cis geometry. The fourth exocyclic diene, sixth dimethylbutadiene and seventh cyclic diene qualify. Thus five of the seven react.
More Pericyclic Reactions and Photochemistry: Electrocyclic, cycloaddition and sigmatropic reactions. Diels-Alder reaction, Claisen and Cope rearrangements and their applications in organic synthesis. FMO method of analysis. Woodward-Hoffmann rules. Photochemistry of alkenes, arenes and carbonyl compounds. Photo-oxidation and photo-reduction. Di-π-methane rearrangements, Norrish type-I and II reactions. Paternό-Büchi reaction, Photo- Curtius and Wolff rearrangements. Barton and Hofmann-Lӧffler-Freytag reactions. questions
GATE 2019 CY Q49– The illustrated unsaturated primary alcohol is treated with PCC and then ZnBr₂. Which…
GATE 2024 CY Q14– The major product in the following reaction sequence is
GATE 2024 CY Q54– Consider the following reaction sequence where M and N are the major products. The correct…
GATE 2025 CY Q27– Choose the correct option(s) with regard to mechanism of the following transformation.
GATE 2026 CY Q38– The correct statement about the intermediate formed in the following reaction is
GATE 2026 CY Q49– The reaction(s) that produce(s) the following compound is(are)
