Showing posts written by Bob Bickler
With the increased use of reversed phase flash chromatography for reaction mixture purification comes a lot of questions since many chemists are not as familiar with this technique as they are with no...
Flash chromatography is a great tool to purify reaction mixtures and natural product extracts. Modern flash chromatography instrumentation incorporates UV detectors to see eluting compounds and trigge...
Silica dissolution in methanol is a concern many chemists have. Over my career I have heard that complaint probably hundreds of times which invariably leads to the question - how much methanol can I u...
Flash chromatography with real-time UV detection and fractionation is the primary tool of chemists for isolating synthetic compounds. However, many commonly used flash chromatography solvents (ethyl a...
If you synthesize organic compounds you likely have encountered situations where traditional silica or even reversed-phase chromatography just does not get the job done. Co-elution, peak tailing, yiel...
For chemists trying to purify polar compound mixtures, optimizing the chromatography can be very challenging. When hexane (or heptane) with ethyl acetate and a silica column fails to effectively purif...
Virtually all automated flash chromatography systems today contain a diode-array UV or UV-vis detector (DAD). This type of UV detector offers multiple benefits over monochromatic UV detectors includin...
Polar reaction mixtures can be a real challenge to purify with flash chromatography. Traditional normal-phase flash requires toxic dichloromethane (DCM) or chloroform with methanol for these types of ...
Silica flash columns are the most frequently used to purify reaction mixtures. Prepacked columns are available from a vast number of vendors as is the silica itself for those wishing to pack their own...
In synthetic organic chemistry, post-reaction work-up using solvent extraction is almost routine. Solvent-solvent extractions using immiscible solvents can remove impurities from the product prior to ...