1.Typical Experimental Conditions & Calculation
Step 1: Screening
To find out which SiliaBond® Metal Scavenger will better suit your need, we recommend performing some screening (on small scale) using the SiliaBond Metal Scavenger Kit (Product # K30730B) to quickly determine which scavenger presents the highest efficiency and make experiment optimization from there.
Step 2: Optimization
If, upon completion of the screening procedure, the scavenging is not completed and you are not satisfied with the scavenging efficiency or you wish to reduce the number of equivalents and the reaction time, the following steps should be undertaken:
- Increase the temperature of the scavenging reaction
- Modify the number of molar equivalents of the SiliaBond Metal Scavenger Change the reaction time
- Try a different and/or a mixture of SiliaBond Metal Scavengers
These parameters can be changed one at a time or simultaneously to improve the metal removal efficiency. It is important to underline that these scavengers are stable and work in any solvent.
SiliaMetS® Thiol (Si-Thiol) is a robust metal scavenger for a variety of metals including Pd, Pt, Cu, Ag and Pb under a wide range of conditions. It has been used in pharmaceutical processes up to the pilot plant scale. It is our most versatile metal scavenger and is the preferred metal scavenger for Pd(II), Cu, Ag, and Hg.
SiliaBond® Amine (Si-NH2) is an effective scavenger of acid chlorides, sulfonyl chlorides, isocyanates and other electrophiles. Si-NH2 has been shown to be effective metal scavenger and catalyst for Knoevenagel reactions. SiliaBond Amine is also used in chromatography as normal phase sorbent.
SiliaMetS® Diamine (Si-DIA) is a proven scavenger for metals and electrophiles. It scavenges acids, acid chlorides, anhydrides, aldehydes, isocyanates, and chloroformates as well as Pb, Ni, and Cd.