Transition-metal-mediated reactions in combinatorial synthesis.

Transition-metal-mediated reactions have played an important role in expanding the scope of combinatorial chemistry from synthesis of peptidic libraries to synthesis of nonoligomeric, small-molecule libraries. Versatile reactions such as heteroannulations, olefin metathesis and dipolar cycloadditions are used for preparation of libraries of historical, as well as novel, pharmacophores. Transition-metal-mediated reactions have also been used strategically to provide traceless linkers' in solid-phase synthesis.