Selective oxidation of tertiary-secondary vic-diols to α-hydroxy ketones by dioxiranes

Curci, Ruggero; D’Accolti, Lucia; Detomaso, Antonia; Fusco, Caterina; Takeuchi, Ken′ichi; Ohga, Yasushi; Eaton, Philip E.; Yip, Yu Chi

doi:10.1016/0040-4039(93)88085-w

Cited by 40 publications

(24 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The hydroxy group of the methanolamine is invoked to direct the DMDO oxidation of the amine to the corresponding N - oxide species 435 . [324] Subsequent collapse of the methanolamine with concomitant loss of p-anisaldehyde and transannular closure of the incipient hydroxylamine on the ketone furnishes 436 . Removal of the TBS protecting group followed by reaction of the primary hydroxy group with trichloroacetyl isocyanate (methanol/silica gel workup) [325] installed the urethane moiety at C13.…”

Section: Successful Total Syntheses Of Fr900482mentioning

confidence: 99%

Mitomycinoid Alkaloids: Mechanism of Action, Biosynthesis, Total Syntheses, and Synthetic Approaches

et al. 2013

View full text Add to dashboard Cite

Section: Successful Total Syntheses Of Fr900482mentioning

confidence: 99%

Mitomycinoid Alkaloids: Mechanism of Action, Biosynthesis, Total Syntheses, and Synthetic Approaches

et al. 2013

View full text Add to dashboard Cite

“…From experimental evidence, 13 it has been established that intermolecular hydrogen bonding plays an important role in the oxidation of vic-diols by dioxiranes. The transition state for the dioxirane C-H insertion is a polar one, 7,13 in which the carbon atom that is oxidized bears a partial positive charge (δ + ), while the hydrogen-bonded oxygen atom of the dioxirane bears a partial negative charge (δ -).…”

Section: Discussionmentioning

confidence: 99%

Asymmetric C−H Oxidation of vic-Diols to α-Hydroxy Ketones by a Fructose-Derived Dioxirane: Electronic Effects on the Enantioselectivity of Oxygen Transfer

1999

View full text Add to dashboard Cite

A mechanistic study on the enantioselective C-H oxidation of vic-diols with the in-situ-generated dioxirane from the fructose-derived ketone 1 is presented. The asymmetrization of meso-configured and the kinetic resolution of racemic vic-diols 2 afforded the optically active R-hydroxy ketones 3 in opposite configurations with moderate to good ee values. Significant electronic effects on the enantioselectivity of C-H insertion have been observed, which are explained in terms of the hydrogen-bonded transition-state structures for the concerted C-H oxygen insertion.

show abstract

“…2 Linear and cyclic 1,2-and 1,3-diols are oxidized by dimethyldioxirane and methyl(trifluoromethyl)dioxirane to c~-and 13-hydroxyketones. [3][4][5][6] The kinetics of the oxidation of cyclohexanol by methyl(trifluoromethyl)dioxirane 1 and that of p-substituted ct-methylbenzyl alcohols by dimethyldioxiranes 2 have been studied. However, the activation parameters have been measured in only a narrow (20 ~ temperature range.…”

mentioning

confidence: 99%

Oxidation of alcohols by dimethyldioxirane

et al. 2000

View full text Add to dashboard Cite

The kinetics of oxidation of a series of monoatomic alcohols (methanol, 2-pro0anol, 2-butanol, 2-methyl-l-propanol, 2-chloroethanol, 1,3-dichloro-2-propanol, benzyl alcohol), hydroxyacetic acid. and t,3-butandiol (ROH) by dimethyldioxirane (1) was studied. The reaction kinetics obeys the second order equation w = k[ROH] [I]. The rate constants were measured in the range of 7--50 ~C. and the activation parameters were found. To describe the reaction rate constants as a function of the ROH structure, the two-parametric Taft equation was used, which takes into account both the polar and resonance substituent effects. Alcohol oxidation produces the corresponding carbonyl compounds, via., ketones from secondary alcohols and aldehydes from primary alcohols, in yields of at least 80%. The results were explained by the competition of the molecular (oxenoid) and radical mechanisms. The introduction of electron-withdrawing substituents into the alcohol molecule increases the contribution of the radical channel of the reaction.Key words: dimethyldioxirane, alcohols, rate constants, free radicals.In recent years, dioxiranes have been widely used for the oxidative functionalization of organic compounds. They possess some advantages as compared to conventional oxidants: mild conditions and high rates of reactions; chemo-, stereo-, and regioseleetivity; simple procedures of oxidation and separation of the reaction products. The reactions between alcohols and dioxiranes have been studied previously, t-6 The reaction between secondary alcohols (viz., propane-2-ol, octane-3-ol, cyclobutanol, cyclohexanol, norborneol, and ct-methylbenzyl alcohol) and methyl(trifluoromethyl)dioxirane affords the corresponding ketones. The oxidation of butan-l-ol by methyl(trifluoromethyl)dioxiranes produces butyric acid, whereas a tertiary alcohol, 2-methylpropan-2-ol, does not react with dioxiranes. 1 The acetophenone derivatives are the main products of the reaction of dimethyldioxirane with p-substituted ct-methylbenzyl alcohols. 2 Linear and cyclic 1,2-and 1,3-diols are oxidized by dimethyldioxirane and methyl(trifluoromethyl)dioxirane to c~-and 13-hydroxyketones. 3-6The kinetics of the oxidation of cyclohexanol by methyl(trifluoromethyl)dioxirane 1 and that of p-substituted ct-methylbenzyl alcohols by dimethyldioxiranes 2 have been studied. However, the activation parameters have been measured in only a narrow (20 ~ temperature range.This work is aimed at the study of the products, kinetics, and mechanism of the interaction between dimethyldioxirane and aliphatie monoatomic alcohols: methanol (2), propan-2-ol (3), butan-2-ol (4), 2-methylpropan-l-ol (5), 2-chloroethanol (6), and 1,3-dichloropropan-2-ol (7), as well as the related compounds: hydroxyacetic acid (8), benzyl alcohol (9), and butane-l.,3-diol (10) (ROH) in an acetone solution at 7.0--50.0 ~ ExperimentalAcetone of high purity grade was purified by distillation. Dimethyldioxirane (1} was synthesized by a known procedureT; water was removed from an acetone solution of dioxirane by free...

show abstract

Selective oxidation of tertiary-secondary vic-diols to α-hydroxy ketones by dioxiranes

Cited by 40 publications

References 25 publications

Mitomycinoid Alkaloids: Mechanism of Action, Biosynthesis, Total Syntheses, and Synthetic Approaches

Mitomycinoid Alkaloids: Mechanism of Action, Biosynthesis, Total Syntheses, and Synthetic Approaches

Asymmetric C−H Oxidation of vic-Diols to α-Hydroxy Ketones by a Fructose-Derived Dioxirane: Electronic Effects on the Enantioselectivity of Oxygen Transfer

Oxidation of alcohols by dimethyldioxirane

Contact Info

Product

Resources

About