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Synthetic Utility of Epoxides for Chiral Functionalization of Isoxazoles.

ABSTRACT: The lithio-anion of isoxazole 2 was found to ring open propylene oxide in good yields with complete regioselectivity. Vinylic and benzylic epoxides were utilized as key examples of electrophiles and found to produce a mixture of regioisomeric adducts. Additionally, the use of chiral epoxides was explored, and absolute configuration was determined by X-ray crystallography to prove that nucleophilic attack at the benzylic carbon of (R)-styrene oxide proceeds with 100% inversion at the benzylic carbon to afford the (S)-alcohol (4b).

SUBMITTER: Nelson JK

PROVIDER: S-EPMC2988249 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Synthetic Utility of Epoxides for Chiral Functionalization of Isoxazoles.

Nelson Jared K JK Burns Christopher T CT Smith Miles P MP Twamley Brendan B Natale N R NR

Tetrahedron letters 20080501 19

The lithio-anion of isoxazole 2 was found to ring open propylene oxide in good yields with complete regioselectivity. Vinylic and benzylic epoxides were utilized as key examples of electrophiles and found to produce a mixture of regioisomeric adducts. Additionally, the use of chiral epoxides was explored, and absolute configuration was determined by X-ray crystallography to prove that nucleophilic attack at the benzylic carbon of (R)-styrene oxide proceeds with 100% inversion at the benzylic car ...[more]

PMID: 21103024

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