5. Scavenging Pd(Dppf)Cl2 Catalyst
Pd(dppf)Cl2 is a new catalyst becoming more and more popular in palladium-catalyzed cross-coupling reaction like Suzuki coupling. This catalyst offers non-negligeable advantages compared to tetrakis(triphenylphosphine)-palladium(0) [Pd(PPh3)4]: more stable, less air-sensitive, and longer shelf-life.
A metal scavenging study using SiliaBond® Metal Scavengers products was conducted on Pd(dppf)Cl2 catalyst. Various parameters were studied for their influence on the scavengers' robustness as well as to establish the best conditions to bring the level of metal down to an acceptable level for the pharmaceutical industry (i.e.: solvent, number of equivalents, temperature, and reaction time).
SiliaMetS® DMT (Si-DMT) is the silica bound equivalent of 2,4,6-trimercaptotriazine (trithiocyanuric acid). It is a versatile metal scavenger for a variety of metals including Cd, Co, Ni, Pd, Pt, Rh, and Ru under a wide range of conditions and the preferred metal scavenger for ruthenium catalysts.
TMT has been reported to efficiently remove palladium and heavy metals by precipitation. Unfortunately, its solubility in organic solvents causes problem. SiliaMetS DMT solves this issue and almost all solvents can now be used.
SiliaSep flash DMT cartridges offer a superior alternative to the other cartridges available on the market.
SiliaPrep Metal Scavengers will lower the residual metal concentration of various metal complexes to single digit ppm.