Synthesis of enol lactones via Cu(I)-catalyzed intramolecular O-vinylation of carboxylic acids.

With the catalysis of CuI/trans-N,N'-dimethylcyclohexane-1,2-diamine, a number of carboxylic acids underwent efficient intramolecular O-vinylation with vinyl bromides leading to the synthesis of the corresponding five- and six-membered enol lactones. The same catalytic system also led to the efficient cycloisomerization of alkynoic acids.

Copper-catalyzed intramolecular N-vinylation of sulfonamides: general and efficient synthesis of heterocyclic enamines and macrolactams.

With the catalysis of CuI/N,N'-dimethylethylenediamine, intramolecular C-N coupling between sulfonamides and vinyl halides was successfully implemented, leading to the efficient synthesis of 5-, 6-, 7-, and even 8-membered heterocyclic enamines in both exo and endo modes. The bicyclic enamines thus formed provided a convenient entry to the corresponding 9- to 12-membered lactams by oxidative C=C bond cleavage.

Sidearm effects in the enantioselective cyclopropanation of alkenes with aryldiazoacetates catalyzed by trisoxazoline/Cu(I).

A highly enantioselective cyclopropanation of alkenes with phenyldiazoacetates catalyzed by CuPF6(CH3CN)4/trisoxazoline has been developed.