Summary of main observation and conclusion A titanium-promoted intramolecular photoenolization/Diels-Alder (PEDA) reaction was developed to construct the core skeleton of aromatic polycyclic terpenoids bearing an all-...Summary of main observation and conclusion A titanium-promoted intramolecular photoenolization/Diels-Alder (PEDA) reaction was developed to construct the core skeleton of aromatic polycyclic terpenoids bearing an all-carbon quaternary center on the benzylic position. Titanium(Ⅳ) isopropoxide [Ti(Oi-Pr)4] plays a key role during the photo cycloaddition, which may help to accelerate the in teraction between dienophile and the stereo-hi ndered diene species as well as control the diastereoselectivity. This photolysis provides a new solution for the stereospecific formation core structures of aromatic abietane diterpenoids and sesquiterpenoids, which have multiple functional groups for the further transformations. As a synthetic application, it was successfully used in the synthesis of indolosesquiterpenoid mycoleptodiscin A.展开更多
基金the National Basic Research Program of China (973 Program 2015CB856600)the National Natural Science Foundation of China (21772044)+1 种基金the "National Young Top-Notch Talent Support Program", Program of Sha nghai Academic/Tech no logy Research Leader (18XD1401500), Program of Shanghai Science and Technology Committee (18JC1411303)"the Fundamental Research Funds for the Central Universities" for generous financial support.
文摘Summary of main observation and conclusion A titanium-promoted intramolecular photoenolization/Diels-Alder (PEDA) reaction was developed to construct the core skeleton of aromatic polycyclic terpenoids bearing an all-carbon quaternary center on the benzylic position. Titanium(Ⅳ) isopropoxide [Ti(Oi-Pr)4] plays a key role during the photo cycloaddition, which may help to accelerate the in teraction between dienophile and the stereo-hi ndered diene species as well as control the diastereoselectivity. This photolysis provides a new solution for the stereospecific formation core structures of aromatic abietane diterpenoids and sesquiterpenoids, which have multiple functional groups for the further transformations. As a synthetic application, it was successfully used in the synthesis of indolosesquiterpenoid mycoleptodiscin A.
