Suzuki, Heck and Sonogishira coupling reactions of paramagnetic 
            vinyl bromides 1-6 gave 
            monofunctional (7a,b), 
            homobifunctional (8a,b, 24), and heterobifunctional pyrroline nitroxides 
            (9-19, 31) under mild conditions in a one-step 
            reaction. From these compounds thiol-specific spin labels 26 and 28 and 
            pyrroline nitroxide annulated heterocycles 30 and 32 were synthesized. The ethynyl derivative 
            of pyrroline nitroxide 33 also can be used 
            as an acetylene reactant in Larock indole synthesis to give the 
            paramagnetic indole derivative 36.
         
            alkynes - free radical - Suzuki reaction - heterocycles - palladium