Example procedures for the conversion of an alkene to a diol using osmium tetroxide (OsO4). Corey-Winter Olefin Synthesis. Diol. Related terms: Ketone; Ligand; Ester; Aldehyde; Epoxide; Alkene…
Diols obtained by osmium tetroxide treatment of porphyrins constitute some of the more complex structures which have been subjected to pinacol rearrangement. While oxidation of the intermediate 1,2-bis(boronate) ester provides a chiral 1,2-diol as the reaction product, homologation/oxidation furnishes a chiral 1,4-diol. The cyclic thiocarbonate is available from reaction of the diol with thiophosgene or thiocarbonyldiimidazole, and reacts with added trimethylphosphite via a syn-elimination to the alkene. There are no carbocation intermediates so rearrangement is not possible. (Z)-1,2-ethenediol is a diol that is ethene substitued at positions 1 and 2 by hydroxy groups (the Z-geoisomer). The anti-hydroxylation of an alkene is accomplished through conversion to the epoxide followed by ring-opening of the epoxide in aquepus acid or base.

Prévost Reaction ... chiral phosphonite ligand. In organic chemistry, an alkene is an unsaturated hydrocarbon that contains a carbon–carbon double bond.Unsaturated hydrocarbons containing two or more double bonds are known as alkadienes, alkatrienes, alkatetraenes, and so on. Related: Name Reactions. Synthesis of diols by dihydroxylation. 1) OsO4 2) NaHSO3 OH OH H H syn addition H H O Os O O O osmate ester intermediate - not usually isolate - NaHSO3breaks down the osmate ester to the product Ozonolysis: oxidative cleavage of an alkene to carbonyl compounds. draw the structure of the diol formed from the reaction of a given alkene … From: Comprehensive Organic Synthesis, 1991. It is an enol and a diol. alkene to give a 1,2-diol. It derives from an ethene . identify the alkene, reagents, or both, that must be used to prepare a given epoxide. It is an enol and a diol. This is an overall oxidation. Conversion of 1,2-diols to alkenes. write the equation for the hydroxylation of an alkene using osmium tetroxide, and draw the structure of the cyclic intermediate. The words alkene and olefin are often used interchangeably (see nomenclature section below).