Selective Ortho C-H Cyanoalkylation Of (Diacetoxyiodo)Arenes Through [3,3]-Sigmatropic Rearrangement

Hypervalent iodine reagents are widely used as unique oxidants,aryl sources,and catalysts in organic synthesis.The iodide atom of aryliodanes is often discarded after these reactions.In recent years,[3,3]-σ rearrangement reactions of aryl iodanes with nucleophiles including β-dicarbonyls,β-naphthols,and allyl/propagyl have attracted great attentions from synthetic community.Unlike traditional hypervalent iodine chemistry,this type of reactions allow the cross-coupling of aryl iodanes with nucleophiles by remaining the aryl iodine moiety in products.The remaining iodide provides versatile platform for further elaboration of products.However,these reactions have long suffered from narrow substrate scope,poor selectivities,and relatively low yields.In this thesis,we describe a new [3,3]-σ rearrangement reaction between aryl iodanes and α-stannyl nitriles,allowing ortho-cyanoalkylation of aryliodanes.We found that the reaction can proceed under-78 °C and complete in less than 5 mins.The extremely low reaction temperature and short reaction time inhibit undesired side reactions and render the reaction excellent functional group compatibility and broad substrate scope.This study provides a new strategy for the development of iodide-remaining couplings of aryl iodanes.