Catalytic,Enantioselective Sulfenylation Of ?-Naphthols

Chiral organosulfur compounds are a very important class of compounds in organic chemistry and also inevitably present in many bioactive natural products and synthetic drugs.In recent years,organic chemists have constantly developed new methodologies to synthesize these compounds and have made remarkable achievements.Among various methods,a very effective approach for the construction of carbon-sulfur(C-S)bonds is the sulfenylation reaction,using electrophilic sulfur reagents.However,the substrate scope for this method is limited.Therefore,it is of great significance to extend the applications of this method.This thesis is divided into two parts.The first part reviewed the research development of organocatalytic sulfenylation reactions.Various active carbonyl compounds such as aldehydes,N-protected oxindoles,?-ketoesters,?-keto phosphonates,?-nitroesters,butyrolactones,as well as some alkenes were employed as substrates for asymmetric sulfenylation reactions.These methods are highly effective in synthesizing chiral organosulfur compounds.The second part is cinchona-derived thiourea catalyzed enantioselective sulfenylation of ?-naphthols.We have developed the first organocatalytic sulfenylation reaction of N-(arylthio)succinimide with ?-naphthols.Various enantioenriched naphthalenones with an S-containing all-substituted stereocenter were prepared via a dearomatization strategy under mild reaction conditions.A varity of ?-naphthols and electrophilic sulfur reagents were obtained with high yields and enantioselectivities.