are readily prepared from the direct reaction between amides and diaryliodonium salts. As demonstrated for 24 different examples, the reaction is of unusually broad scope with respect to the sterically congested arene and the nitrogen source, occurs without the requirement for any additional promoter, and proceeds through a direct reductive elimination at the iodine(III) center. The efficiency of the
A series of sterically hindered (methoxylated) polychlorinated biphenylderivatives were synthesized using the Suzuki and the Ullmann coupling reactions. The Suzuki coupling with Pd(dba)2/2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (DPDB) gave better yields (65-98%) compared to the classic Ullmann coupling reaction (20-38%). Despite the reactive catalyst system, no significant coupling with aromatic
In the course of a programme aimed at discovering new ligands of the estrogen receptor, we explored a series of substituted biphenyls. Their synthesis and binding affinity are described.
Physical, spectral and chromatographic data for all 209 individual PCB congeners is presented. The individual congeners were synthesized and then isolated and purified. Recent emphasis on the source of the toxicity of commercial PCB formulations has increased the need for a complete set of the PCB congeners. Through the use of two capillary GC columns: 40% octadecyl/ 15% phenyl methyl siloxane and 50% phenyl methyl siloxane, it was possible to separate 201 PCB congeners with only four unresolved pairs. The data compiled in this study for all 209 congeners will aid in the identification of selected individual components of these environmental pollutants. The use of this data also presents the opportunity for the improved quantification of the commercial PCB formulations.