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Intramolecular Diels-Alder Reaction of a Biphenyl Group in a Strained meta-Quaterphenylene Acetylene.

ABSTRACT: At elevated temperatures, a strained, cyclic meta-quaterphenylene acetylene undergoes an intramolecular cyclization reaction to form benz[e]indeno[1,2,3-hi]acephenanthrylene. This reaction represents an example of a Diels-Alder reaction at the 2-, 1-, 1'-, and 2'-positions of a biphenyl derivative, a region analogous to the bay regions of perylene and other periacenes. The reaction proceeds cleanly with high conversion. Kinetics studies of a methylated derivative reveal that the ΔG^‡ for the reaction is ∼40-41 kcal/mol, and computational models predict a similar value of G_rel for the transition state of a concerted [4 + 2]-cycloaddition.

SUBMITTER: Mittal K

PROVIDER: S-EPMC11232012 | biostudies-literature | 2024 Jul

REPOSITORIES: biostudies-literature

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Intramolecular Diels-Alder Reaction of a Biphenyl Group in a Strained meta-Quaterphenylene Acetylene.

Mittal Komal K Pham Ashley V AV Davis Amanda G AG Richardson Abigail D AD De Hoe Clement C Dean Ryan T RT Baird Vi V McDonald Ashley Ringer AR Frantz Derik K DK

The Journal of organic chemistry 20230126 13

At elevated temperatures, a strained, cyclic meta-quaterphenylene acetylene undergoes an intramolecular cyclization reaction to form benz[e]indeno[1,2,3-hi]acephenanthrylene. This reaction represents an example of a Diels-Alder reaction at the 2-, 1-, 1'-, and 2'-positions of a biphenyl derivative, a region analogous to the bay regions of perylene and other periacenes. The reaction proceeds cleanly with high conversion. Kinetics studies of a methylated derivative reveal that ...[more]

PMID: 36701431

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