Counteranion-directed catalysis in the Tsuji-Trost reaction: stereocontrolled access to 2,5-disubstituted 3-hydroxy-tetrahydrofurans.

Hydrogen bonds can play a prominent role in organometallic catalysis, as shown for the title reaction, in which a counteranion directs the cyclization through the formation of hydrogen bonds that likely involve a proton of the π-allyl/palladium species itself. The reaction allows access to four out of the eight stereoisomers of 2,5-disubstitued 3-hydroxy-tetrahydrofurans and thus fragments of complex natural products.