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Wittig Rearrangements of Boron-Based Oxazolidinone Enolates.

ABSTRACT: [2,3]-Sigmatropic rearrangements (Wittig rearrangements) of ?-alkoxy oxazolidinone enolates are described. Whereas alkali metal enolates fail, owing to facile deacylation, boron enolates generated from di-n-butylboron triflate and triethylamine rearranged in good yields and high selectivities with exceptions noted. IR and NMR spectroscopies show the boron is chelated by the ?-alkoxy group rather than the more distal oxazolidinone carbonyl in the complex and enolate. The rearrangement product contains a boron alkoxide that remains unchelated by either carbonyl. Optimization was guided by density functional theory computations, suggesting that valine-derived oxazolidinones would be superior to the phenylalanine-derived analogues.

SUBMITTER: Zhang Z

PROVIDER: S-EPMC7050190 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Wittig Rearrangements of Boron-Based Oxazolidinone Enolates.

Zhang Zirong Z Collum David B DB

The Journal of organic chemistry 20190815 17

[2,3]-Sigmatropic rearrangements (Wittig rearrangements) of α-alkoxy oxazolidinone enolates are described. Whereas alkali metal enolates fail, owing to facile deacylation, boron enolates generated from di-n-butylboron triflate and triethylamine rearranged in good yields and high selectivities with exceptions noted. IR and NMR spectroscopies show the boron is chelated by the α-alkoxy group rather than the more distal oxazolidinone carbonyl in the complex and enolate. The rearrangement prod ...[more]

PMID: 31414796

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