Stereoselective Formation of Substituted 1,3-Dioxolanes through a Three-Component Assembly during the Oxidation of Alkenes with Hypervalent Iodine(III)

Stereoselective formation of substituted 1,3-dioxolanes was achieved through an assembly of three components: alkene, carboxylic acid and silyl enol ether. The reaction proceeded via stereospecific generation of a 1,3-dioxolan-2-yl cation intermediate during oxidation of alkene substrates with hypervalent iodine. The stereoselective trapping of the cation intermediate with silyl enol ether completed the formation of the dioxolane product

Enantioselective dioxytosylation of styrenes using lactate-based chiral hypervalent iodine(III)

A series of optically active hypervalent iodine(III) reagents prepared from the corresponding (R)-2-(2-iodophenoxy)propanoate derivative was employed for the asymmetric dioxytosylation of styrene and its derivatives. The electrophilic addition of the hypervalent iodine(III) compound toward styrene proceeded with high enantioface selectivity to give 1-aryl-1,2-di(tosyloxy)ethane with an enantiomeric excess of 70–96% of the (S)-isomer

Enantioselective C–C Bond Formation during the Oxidation of 5‑Phenylpent-2-enyl Carboxylates with Hypervalent Iodine(III)

The oxidation of (5-acyloxypent-3-enyl)­benzene with hypervalent iodine­(III) afforded 2-oxy-1-(oxymethyl)­tetrahydronaphthalene under metal-free conditions. The acyloxy group may nucleophilically participate in the oxidative cyclization. A lactate-based chiral hypervalent iodine afforded an enantioselective variant of oxyarylation with up to 89% ee

A Series of Two Oxidation Reactions of <i>ortho</i>-Alkenylbenzamide with Hypervalent Iodine(III): A Concise Entry into (3<i>R</i>,4<i>R</i>)‑4-Hydroxymellein and (3<i>R</i>,4<i>R</i>)‑4-Hydroxy-6-methoxymellein

A sequence of oxidation reactions of alkenamides with hypervalent iodine is described. Oxidation of <i>ortho</i>-alkenylbenzamide substrates selectively gave isochroman-1-imine products. The products underwent further oxidation in the presence of a Pd salt catalyst leading to regioselective C–H acetoxylation at the 8-position. A series of oxidations was applied to the crucial steps of asymmetric synthesis of 4-hydroxymellein derivatives