Different Ways of Removing Rhodium

For the synthesis of Active Pharmaceutical Ingredients (API), rhodium is one of the catalysts of choice. According to the International Council for Harmonization (ICH) guidelines, leftover metallic and elemental impurities should be reduced below a certain amount from the final products.
This Application Note details different options to minimize residual rhodium contamination in a crude product: silica gel chromatography (SiliaFlash), activated carbon (SiliaCarb), metal scavengers (SiliaMetS) and radial flow cartridges (E-PAK).

Find below the list of SiliCycle's products involved in this Application Note:
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SiliaMetS Triamine (R48030B)
Effective for scavenging metals such as Pb, Co, Ru and Pd. Our screening studies have shown it to be the preferred scavenger for Pb. It can also be used as a scavenger for acid chlorides, isocyanates and other electrophiles. -
SiliaMetS Diamine (R49030B)
SiliaMetS is a proven scavenger for metals and electrophiles. It scavenges acids, acid chlorides, anhydrides, aldehydes, isocyanates, and chloroformates. Best metal scavenger for: Cr, Pd, Pt, W & Zn. Good scavenger for: Cd, Co, Cu, Fe, Hg, Ni, Pb, Ru, Sc, Se & V. -
SiliaMetS Thiol (SH) Metal Scavenger (R51030B)
Our most versatile and robust metal scavenger for a variety of metals under a wide range of conditions. Best scavenger for: Ag, Hg, Os, Pd & Ru. Good scavenger for: Cu, Ir, Pb, Rh, Se & Sn. -
SiliaMetS TAAcONa nec (R69230B)
SiliaMetS TAAcONa or (or SiliaMetS Triaminetetraacetate, sodium salt) is a silica bound metal scavenger for Pd(II), Ni(II) and Cu. It is the supported version of EDTA in its sodium salt form. It is an effective scavenger for metals in higher oxidation state, 2+ or higher. -
SiliaMetS Thiourea (THU) (R69530B)
SiliaMetS Thiourea (Si-THU) is a versatile metal scavenger for all forms of palladium, and is widely used in the pharmaceutical industry. Once complexed with a transition metal, it has also been reported as being an effective catalyst. Best scavenger for: Pd & Ru. Good scavenger for: Ag, Cu, Fe, Os, Rh, Sc & Sn. -
SiliaMetS DMT (Dimercaptotriazine) (R79030B)
SiliaMetS DMT is the silica - bound equivalent of 2,4,6 - trimercaptotriazine (trithiocyanuric acid, TMT). It is a versatile metal scavenger for a variety of metals and the preferred metal scavenger for ruthenium catalysts and hindered Pd complexes. Best scavenger for: As, Ir, Ni, Os, Pd, Pt, Rh, Ru & Se. Good scavenger for: Cd, Co, Cu, Fe, Sc & Zn. -
SiliaMetS Imidazole (IMI) (R79230B)
SiliaMetS Imidazole (Si-IMI) is a versatile metal scavenger for a variety of metals under a wide range of conditions and the preferred metal scavenger for iron catalysts. Best scavenger for: Cd, Co, Cu, Fe, Ir, Li, Mg, Ni, Os, W & Zn. Good scavenger for: Cr, Pd & Rh. It can also be used as an amine base in systems that are generally sensitive to basic conditions compared to other SiliaMetS supported bases. -
SiliaMetS Cysteine (CYS) (R80530B)
SiliaMetS Cysteine (Si-Cys) is the silica bound equivalent of the amino acid Cysteine. It is a versatile metal scavenger for a variety of metals including Pd, Sn, Ru, Pt, Cu, Rh, Cd and Sc under a wide range of conditions and the preferred metal scavenger for tin residues. -
SiliaMetS AMPA (R85130B)
SiliaMetS AMPA is an aminomethylphosphonic acid ligand known for its excellent metal-bonding properties. It's the first AMPA silica-supported on the market and a very powerful tool to scavenge Lanthanides. Best scavenger for: Al, Ce, Gd, La, Ni, Sb & V. Good scavenger for: Co, Cu, Fe, M & Zn. -
SiliaMetS DEAM (R54430B)
SiliaMetS DEAM is a versatile scavenger designed to remove trace metal or boronic acids from reaction intermediates or final APIs. Best scavenger for: Ag, Fe, Sn, Ti & Zn. Good scavenger for: Se.