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Asymmetric synthesis of 2-substituted oxetan-3-ones via metalated SAMP/RAMP hydrazones.

ABSTRACT: 2-Substituted oxetan-3-ones can be prepared in good yields and enantioselectivities (up to 84% ee) by the metalation of the SAMP/RAMP hydrazones of oxetan-3-one, followed by reaction with a range of electrophiles that include alkyl, allyl, and benzyl halides. Additionally, both chiral 2,2- and 2,4-disubstituted oxetan-3-ones can be made in high ee (86-90%) by repetition of this lithiation/alkylation sequence under appropriately controlled conditions. Hydrolysis of the resultant hydrazones with aqueous oxalic acid provides the 2-substituted oxetan-3-ones without detectable racemization.

SUBMITTER: Geden JV

PROVIDER: S-EPMC3954718 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of 2-substituted oxetan-3-ones via metalated SAMP/RAMP hydrazones.

Geden Joanna V JV Beasley Benjamin O BO Clarkson Guy J GJ Shipman Michael M

The Journal of organic chemistry 20131111 23

2-Substituted oxetan-3-ones can be prepared in good yields and enantioselectivities (up to 84% ee) by the metalation of the SAMP/RAMP hydrazones of oxetan-3-one, followed by reaction with a range of electrophiles that include alkyl, allyl, and benzyl halides. Additionally, both chiral 2,2- and 2,4-disubstituted oxetan-3-ones can be made in high ee (86-90%) by repetition of this lithiation/alkylation sequence under appropriately controlled conditions. Hydrolysis of the resultant hydrazones with a ...[more]

PMID: 24152298

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