Pd(Ⅱ)-Catalyzed Oxypalladation Of Alkynes And Desymmerizing Malononitriles Addition Cascade Reaction

Tetrahydrobenzoisocoumarins are widely used as key intermediates for the synthesis of some complex molecules,and it is of great significance to develop efficient methods to synthesize the compounds.This thesis mainly focused on the synthesis ofβ-quaternary carbon-containing tetrahydrobenzoisocoumarins through palladium-catalyzed oxypalladation of alkynes and desymmerizing malononitriles addition cascade.This cascade strategy constructed two rings and an all-carbon quaternary stereocenter in a single operation using Pd（TFA）₂/（S）-^tBu Phox as catalyst under acidic conditions with good yields（34–75%）and enantioselectivities（85:15–99:1 er）.To highlight the practicality,a gram-scale reaction and product derivatizations were carried out.The method provided a new strategy for the synthesis of asymmetry tetrahydrobenzoisocoumarins...