Studies On The Aerobic Oxidation Of Allenes By The Visible Light Photocatalysis

The visible light has the characteristics of green,easily available,natural abundance and etc.,which has been paid much attention by chemical scientists in recent years.Using of visible light photocatalysis directly in organic synthesis is not only in accordance with the concept of green chemistry,but also could obtain the products which are difficult to get by the route of traditional catalysis.Allenes possessing two adjacent perpendicular π orbitals have the unique reactivity and diverse transformation abilities.Based on these,if the novel visible-light photocatalytic mode instead of traditional catalytic modes(such as acid or base catalysis,transition metal catalysis)can be applied to the reaction of allenes,its research will have a certain scientific significance and potential application value.Thus,in this paper the transformation of allenes under the visible light photoctalysis was mainly studies and discussed.This paper was divided into three subsections:The first chapter is a review of visible light photocatalysis.Although the current reaction based on visible light catalysis is too numerous to mention in detail,the visible light photocatalysis directly applied to the chemical reactions of allenes rarely reported.So in this chapter,some progress in the study of olefins in recent years by visible light photocatalysis is mainly reviewed,and then few examples about visible light photoctalytic reactions of allenes were discussed.In the second chapter,it is found that the C=C double bond of aromatic-substituted allenes compounds with rich electrons can be oxidized irreversibly cleavage to the corresponding aldehydes and ketone compounds by the Ir(III)complexes under visible light and O2 atmosphere.While the relatively simple phenyallene could be converted to 1,2-dione compounds under the similar conditions.In the third chapter,the allylic carbon anion obtained by iodine ion nucleophilic attack of electron-deficient allenones could be oxidized in the visible light catalysis system.And subsequently allylic radical was captured by oxygen,which supplied a new way for the synthesis of novel 2-iodo-2-ene-1,4-dione compounds.Similar allenoates are also compatible with this reaction system.The products containing multiple functional groups thus have important application values not only in subsequent chemical transformations,but also the products were firstly synthesized via visible light photocatalytic mode.