US Patent 7220884 Hydroaminomethylation of olefins

The present invention relates to a method comprising the step of contacting under hydroaminomethylation conditions, an olefin, an amine, a rhodium-phosphorous ligand, and synthesis gas (syngas). In particular, it has been discovered that, under some circumstances, a neutral rhodium-monodentate phosphite ligand is prescribed. The invention provides a simple way of making, in high yields and regiospecificity, a variety of products, including pharmacologically active products such as ibutilide, terfenadine, and fexofenadine, and derivatives thereof.