The hydrogenation of three different pharmaceutical nitro-containing compounds has been studied using high-throughput
experimentation (HTE) methods. Significant improvements to
the existing reactions were obtained for two of the examples.
Each reaction exhibits distinct features regarding activity and
chemoselectivity. The best catalyst and reaction conditions
found were remarkably different for each of the reactions. For
one of the reactions, larger-scale studies are presented, which
show that the screening reactions provided a fast and reliable
indicator of the most promising reaction conditions.
The development of a synthetic process for (S,S)-reboxetine succinate, a candidate for the treatment of fibromylagia, is disclosed from initial scale-up to deliver material for registrational stability testing through to commercial route evaluation and subsequent nomination. This entailed evaluation of several alternative routes to result in what would have been a commercially attractive process for launch of the compound.
The Pfizer Green Chemistry metrics program is described and exemplified with a case history involving the synthesis of (S,S)-reboxetine succinate. The initial route used a classical resolution approach and generated high levels of waste. This route was replaced by an enantiospecific synthesis which used Sharpless epoxidation chemistry, an enzymatic process to selectively protect a primary alcohol and a new efficient method of chiral morpholine construction as key steps. These improvements reduced the levels of waste produced by the synthesis by more than 90%. Detailed metrics starting from a common starting material (trans-cinnamyl alcohol) for all routes of synthesis are presented.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.