Studies On Palladium-catalyzed Cyclization Reaction Of Phenol And Its Derivatives

Chapter ?In part one,phenol and its derivatives are very important starting materials for organic synthesis and also play a key role in the field of cycloaddition and dearomatization.Through a direct cyclization we can obtain a series of benzo ring compounds,and under dearomatization we can convert planar aromatic rings into highly functional three-dimensional structures.We herein systematically summarize the cyclization reaction and dearomatization reaction of phenol and its derivatives.In part two,the use of enyne cyclization is an efficient and direct strategy to construct polycyclic framework compounds.Traditional methods of constructing polycyclic compounds have been achieved primarily through multi-step reactions or the synthesis of complex substrates.However,the use of enynes compounds can achieve this target through a domino reaction strategy.Here,we systematically summarize the method of synthesizing three-dimensional polycyclic framework compounds by using enynes as substrates in combination with a domino reaction strategy.In part three,the decarboxylative allylation reaction is a very significant branch of the decarboxylation coupling reactions,which utilize decarboxylative metalation to generate organometallic intermediates that are coupled via reductive elimination.This method is also applied into the cycloaddition reaction.In addition,decarboxylation allows the site-specific generation and coupling of reactive intermediates with higher regioselectivity in contrast to the C-H bond activation.Therefore,we systematically summarize the research progress of decarboxylative allylation.Chapter ?Using the dearomatization ability of phenol derivatives and the cyclization of enyne substrates,we realized palladium-catalyzed [2+2+1] cycloaddition domino reaction and constructed a series of tetracyclic scaffolds with spiro units.This reaction is compatible with the synthesis of a variety of heterocyclic backbones.Meanwhile,this novel method has potential application value in the synthesis of natural products and pharmaceutical molecules.Chapter ?The use of ligand to tune the regioselectivity is a simple,efficient,economical but challenging strategy.We utilize free naphthols and easily prepared vinylethylene carbonates to achieve high regio-and chem-selective decarboxylate allylation of [3+2] and [3+3] cycloaddition reactions by palladium/ligand catalysis.Both 1-naphthol and 2-naphthol can be applied to this method to maximize the diverse synthesis.