PALLADIUM-PROMOTED COUPLING REACTIONS OF [C-11] METHYL-IODIDE WITH ORGANOTIN AND ORGANOBORON COMPOUNDS

Methods for the rapid incorporation of C-11 (beta(+), t1/2 = 20.3 min) into a number of compounds have been developed. By the use of palladium-promoted cross-coupling of [C-11]methyl iodide with organostannanes, the model compounds [alpha-C-11]toluene, methyl 4-[C-11]methylbenzoate and [1-C-11]propene were obtained in 4 min reaction time. Synthesis of [1-C-11]heptane was achieved by reaction of [C-11]methyl iodide with 9-hexyl-9-borabicyclo[3.3.1]nonane in the presence of Pd(0). The radiochemical yields were between 40 and 85% before purification and the decay-corrected radiochemical yields of isolated products were 30-54%, based on [C-11]methyl iodide.