Enantioselective Ammonium Ylide Mediated One‐Pot Synthesis of Highly Substituted γ ‐Butyrolactones

An access to highly enantioenriched cis-3,5-disubstituted γ-lactones from α-bromoacetate and silyl enol ether

A novel synthetic strategy for highly enantioenriched cis-3,5-disubstituted γ-lactones has been developed by the AgOTf-promoted nucleophilic substitution of α-bromoacetates with silyl enol ethers and subsequent reductive lactonization. The utility of this synthetic method was further demonstrated through the concise stereodivergent synthesis of cis- and trans-2,4-disubstituted tetrahydrofurans.

Asymmetric Construction of α-Substituted β-Hydroxy Lactones via Ni Catalyzed Decarboxylative Addition Reaction

We described a Ni-bidentate oxazoline catalyzed highly enantio- and diastereoselective decarboxylative aldol reaction of 2-oxotetrahydrofuran-3-carboxylic acid/2-oxochromane-3-carboxylic acid derivatives with different kinds of carbonyls. Under optimal reaction conditions, α-substituted β-hydroxy butyrolactones and dihydrocoumarins with an all-carbon quaternary stereocenter have been generated with high levels of functional-group compatibility. Furthermore, proficient transformations of products were also described, in which an aliphatic tertiary alcohol and a multi-substituted 1,4-diol were smoothly constructed through hydrogenation and ring-opening reaction, respectively.

Synthesis of disubstituted γ-butyrolactones and spirocyclopropanes via a multicomponent reaction of aldehydes, Meldrum's acid and sulfoxonium ylides

An efficient synthesis of disubstituted γ-butyrolactones and spirocyclopropanes via multicomponent reaction of aldehydes, Meldrum's acid and sulfoxonium ylides has been developed.