Construction Of Multi-functional Fused Arenes From Tetraynes And Phosphorus Ylide Reagent Reaction

The benzyne intermediate has a strong reaction activity and good regional selectivity.It has unique advantages in the construction of cyclic compounds,especially in certain complex dense ring compounds.Organophosphine reagents can be widely used in the conversion of functional groups in molecular structures,modification of molecular functions,formation of catalytic C—C bonds,and the like.We reacted HDDA with tetrayne as the substrate,and reacted with ylide reagent in the absence of a catalyst to obtain a polyfunctional compound with an aromatic ring backbone.This synthetic strategy breaks through the conventional method of building carbon-carbon double bonds by P-ylide reagent.The main research contents of this article include the following three parts:1.Construction of polyfunctional fused aromatics by tetraynes and phosphine ylidesThe HDDA cyclization reactions of palladium-catalyzed tetraynes derivatives and P-ylide were studied.Through the optimization of the reaction conditions,we developed a mild catalyst-free synthesis of polyfunctional fused aromatics in good to excellent yields.This method was simple,also accorded with the requirement of atom economy of green chemistry.It was verified that H₂O played a crucial role in this reaction.With this novel method,the methylation and carbonylation of aromatic rings are simultaneously achieved.Twenty-five polyfunctionalized fused aromatic derivatives were generated through the study of the tandem HDDA reaction of different P-ylide and tetraynes substrates.We proposed the possibly mechanism of the reaction,tetraynes substrates formed benzyne intermediates by self-cyclization then reacted with P-ylide and to get the fused aromatics structure compounds through the HDDA reaction.2.Construction of Multi-functional Fused benzofuran derivatives from Tetraynes and phosphorus ylideTwo series of differently substituted benzofuran derivatives were constructed by series reaction of HDDA with different tetrayne substrates and two different P-ylide reagents.The reaction is simple,the product is easy to separate and purify,and the method is novel.It provides a brand-new practical and efficient method for synthesizing polysubstituted fused benzofuran derivatives.P-ylide reacted directly with various substituents?p-F,p-CH3,p-CH₂CH₃,o-Cl?tetraynes derivatives.Tetraynes derivatives and P-ylide derivatives could effectively react at 100?produced 16 multi-functional fused benzofuran derivatives.Furthermore,the cyclization reactions of palladium-catalyzed tetraynes derivatives and P-ylide were studied.3.The Alder-ene reaction of Tetraynes and TheaspiraneIn the absence of a metal catalyst,no oxidizing agent,no additives,and no protection,the carbon atom-bridged tetrayne substrates is reacted with the theaspirane in the Alder-ene reaction,and the fusedaromatic hydrocarbon spiro derivative is completed in one step.The construction breaks through the limitations of metal catalysis,which achieves the same effect in the presence of alkali.9 S-configurations and 10R-configurations of fused aromatic spirocyclic derivatives were synthesized.The structures of X-rays with S and R configurations were obtained.This reaction undergoes a HDDA-type reaction to form a tetrayne intermediate and an alder-ene reaction occurs with the tetrayne intermediate as an enophile and the allyl moiety in the alprasol to obtain the final product.All compounds were characterized by ¹H NMR,¹³C NMR,IR,and HRMS,structures of some products were also confirmed by X-ray single crystal structure analysis.