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A Chiral Thiourea as a Template for Enantioselective Intramolecular [2 + 2] Photocycloaddition Reactions.

ABSTRACT: A chiral (1R,2R)-diaminocyclohexane-derived bisthiourea was found to exhibit a significant asymmetric induction in the intramolecular [2 + 2] photocycloaddition of 2,3-dihydropyridone-5-carboxylates. Under optimized conditions, the reaction was performed with visible light employing 10 mol % of thioxanthone as triplet sensitizer. Due to the different electronic properties of its carbonyl oxygen atoms, a directed binding of the substrate to the template is possible, which in turn enables an efficient enantioface differentiation.

SUBMITTER: Mayr F

PROVIDER: S-EPMC4994062 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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A Chiral Thiourea as a Template for Enantioselective Intramolecular [2 + 2] Photocycloaddition Reactions.

Mayr Florian F Brimioulle Richard R Bach Thorsten T

The Journal of organic chemistry 20160609 16

A chiral (1R,2R)-diaminocyclohexane-derived bisthiourea was found to exhibit a significant asymmetric induction in the intramolecular [2 + 2] photocycloaddition of 2,3-dihydropyridone-5-carboxylates. Under optimized conditions, the reaction was performed with visible light employing 10 mol % of thioxanthone as triplet sensitizer. Due to the different electronic properties of its carbonyl oxygen atoms, a directed binding of the substrate to the template is possible, which in turn enables an effic ...[more]

PMID: 27258626

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