| SYNTHESIS |
are versatile substrates for 1,3-dipolar additions in constructing biologically active heterocycles. They usually are made by multistep synthesis, but now, Bruce A. Arndtsen, an associate professor of chemistry at McGill University, Montreal, and coworkers have come up with an easier way [J. Am. Chem. Soc., 125, 1474 (2003)]. Using a commercially available palladium catalyst, they assemble münchnones from the coupling of an imine, an acid chloride, and carbon monoxide in one pot (reaction shown). In the same pot, the product is converted further by the addition of appropriate reagents. For example, the researchers have demonstrated that adding an alcohol to the pot yields amido esters. Arndtsen says other useful products can be accessed with other reagents--for example, alkynes to yield pyrroles, imines to form -lactams, and nitriles or N-tosyl imines to make imidazoles.
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