The ideal reaction for an industrial chemist, Nobel Laureate Sir John W. Cornforth said humorously in 1975, “is something to be carried out in a disused bathtub by a one-armed man who cannot read, the product being collected continuously through the drain hole in 100% purity and yield.” Rare is the reaction that clears that bar, but a team at the University of St. Andrews, in Scotland, is giving it their best shot. They’ve developed a continuous hydrogenation that requires no solvent and yields a nearly enantiomerically pure product (Angew. Chem. Int. Ed. 2013, DOI: 10.1002/anie.201302718). Similar hydrogenations require supercritical carbon dioxide solvent. Solventless reactions, however, can reduce costs and waste. Rubén Duque, Peter J. Pogorzelec, and David J. Cole-Hamilton anchored a chiral rhodium catalyst to alumina using phosphotungstic acid. They packed the alumina into a 10-mL steel column and pumped substrate and hydrogen gas through it. At ambient temperature and roughly 5-atm pressure, they collected (S)-(–)-dibutyl 2-methylsuccinate directly from the reactor in 98% enantiomeric excess. The product elutes with 45-ppb rhodium, which leaches from the reactor. The reaction’s enantioselectivity decreases after 23 hours. The team is working on making the catalyst more stable.