Abstract
A detailed mechanistic understanding of the malonoyl peroxide mediated dihydroxylation of alkenes is presented. The reaction is first order in both alkene and peroxide with stoichiometric water playing a dual role. An ionic mechanism is proposed and supported by the use of 18O isotopically labelled peroxide, a radical clock probe and DFT calculations. Hammett analysis suggests the reaction proceeds via a discrete carbocation intermediate which is consistent with the stereochemical outcome of the transformation. A subsequent Woodward-type 1,3-dioxolan-2-yl cation has been trapped in situ and the mechanism of hydrolysis defined by isotopic labelling studies. Stable reaction intermediates have been isolated and characterised by X-ray crystallographic analysis and minor competing reaction pathways identified.
Original language | English |
---|---|
Pages (from-to) | 1777-1785 |
Number of pages | 9 |
Journal | Chemical Science |
Volume | 5 |
Issue number | 5 |
Early online date | 19 Feb 2014 |
DOIs | |
Publication status | Published - 1 May 2014 |
Keywords
- stoichiometric water
- hydrolysis
- discrete carbocation