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Novel asymmetric photodimerization reaction of coumarin derivatives bearing a chiral 2-oxazolidinone auxiliary.

ABSTRACT: A novel asymmetric photodimerization reaction of coumarin derivatives bearing the (S)-4-benzyl-2-oxazolidinone auxiliary provides only the syn-head-to-tail (syn-HT) dimer with moderate diastereoselectivity (up to 75 : 25). The mechanism of complete syn-HT selectivity and moderate diastereoselectivity is proposed based on the result of density functional theory (DFT) calculation. The benzyl group of the (S)-4-benzyl-2-oxazolidinone auxiliary in combination with a Lewis acid exerts effective diastereofacial shielding of the reaction site.

SUBMITTER: Itoh K

PROVIDER: S-EPMC9063662 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Novel asymmetric photodimerization reaction of coumarin derivatives bearing a chiral 2-oxazolidinone auxiliary.

Itoh Kennosuke K Odate Fumiya F Karikomi Takuma T Obe Keishi K Miyamori Tsutomu T Kamiya Hideaki H Yoza Kenji K Nagai Kenichiro K Fujii Hideaki H Suga Hiroyuki H Tokunaga Ken K

RSC advances 20190423 22

A novel asymmetric photodimerization reaction of coumarin derivatives bearing the (S)-4-benzyl-2-oxazolidinone auxiliary provides only the syn-head-to-tail (syn-HT) dimer with moderate diastereoselectivity (up to 75 : 25). The mechanism of complete syn-HT selectivity and moderate diastereoselectivity is proposed based on the result of density functional theory (DFT) calculation. The benzyl group of the (S)-4-benzyl-2-oxazolidinone auxiliary in combination with ...[more]

PMID: 35515875

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