Asymmetric Heck reaction of (R) 1-tert-butylsulfinylcyclopentene with arenediazonium salts

The asymmetric Heck reaction of the readily available (A) 1-tert-butylsulfi nyl-1-cyclopentene with a variety of para- and meta- substituted arenediazo nium tetrafluoroborates is described. In the presence of Ag2CO3 as base, in CH3CN at rt, the reactions occur in good yields (72-79%) with high diaster eoselectivities (de = 82-92%) to afford (3S, SR)-3-aryl-2-tert-butylsulfiny l-1-cyclopentenes as the major adducts. In contrast, poor results were obta ined from ortho-substituted arenediazonium salts.