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Solvent Systems for Silica Gel Column Chromatography








EtOAc

Solvent System Examples Comments
EtOAc -- As a one component solvent system there is no ability to create a gradient. It still may be useful for easy separations.
EtOAc/hexane 25-40% EtOAc/hexane   [see procedure]
0-10% EtOAc/hexane   [see procedure]
20-100% EtOAc/hexane   [see procedure]
10-50% EtOAc/hexane   [see procedure]
50% EtOAc/hexane   [see procedure]
Very common solvent system. Heptane is generally recommended as a replacement for hexane because of its lower toxicity.
EtOAc/heptane 1:2 EtOAc/heptane   [see procedure]
30-80% EtOAc/heptane   [see procedure]
10-100% EtOAc/heptane   [see procedure]
0-25% EtOAc/heptane   [see procedure]
5-20% EtOAc/heptane   [see procedure]
Similar to EtOAc/hexane. Heptane is a less toxic alternative for hexane.
EtOAc/PE 2:1 PE/EtOAc   [see procedure]
5:1 PE/EtOAc   [see procedure]
0-25% EtOAc/PE   [see procedure]
1:1 PE/EtOAc   [see procedure]
10:1 PE/EtOAc   [see procedure]
The low boiling point (high vapor pressure) of PE increases flammability concerns. It is one of the only solvent systems where the less polar solvent is typically written first (i.e. PE/EtOAc).
EtOAc/DCM 20-100% EtOAc/DCM   [see procedure]
0-50% EtOAc/DCM   [see procedure]
30-100% EtOAc/DCM   [see procedure]
An option for compounds that have good solubility in DCM, but don't move much on silica at 100% DCM.
EtOAc/cyclohexane 0-25% EtOAc/cyclohexane   [see procedure]
30-50% EtOAc/cyclohexane   [see procedure]
0-50% EtOAc/cyclohexane   [see procedure]
0-100% EtOAc/cyclohexane   [see procedure]
Cyclohexane (similar to heptane) is a less toxic alternative for hexane.
EtOAc/pentane 20% EtOAc/pentane   [see procedure]
30% EtOAc/pentane   [see procedure]
5% EtOAc/pentane   [see procedure]
Pentane (similar to heptane) is a less toxic alternative for hexane. However, a low boiling point (high vapor pressure) increases flammability concerns.
EtOAc/DCM/hexane -- Three solvent system.

MeOH

Solvent System Examples Comments
MeOH/DCM 0-3% MeOH/DCM   [see procedure]
0-10% MeOH/DCM   [see procedure]
0-16% MeOH/DCM   [see procedure]
2% MeOH/DCM   [see procedure]
2-5% MeOH/DCM   [see procedure]
Very common solvent system.
MeOH/CHCl3 0-1% MeOH/CHCl3   [see procedure]
3% MeOH/CHCl3   [see procedure]
2% MeOH/CHCl3   [see procedure]
1:9 MeOH/CHCl3   [see procedure]
Similar to MeOH/DCM.
MeOH/EtOAc 0-5% MeOH/EtOAc   [see procedure]
5% MeOH/EtOAc   [see procedure]
Considered a 'greener alternative' to MeOH/DCM since it replaces DCM with EtOAc.
MeOH/DCM/hexane -- Three solvent system.
MeOH/DCM/heptane -- Similar to MeOH/DCM/hexane. Three solvent system. Heptane is a less toxic alternative for hexane.
MeOH/DCM/EtOAc -- Three solvent system.
MeOH/DCM/ether 100% DCM to 60:35:5 DCM/ether/MeOH
    [see procedure]
Three solvent system. Diethyl ether presents flammability concerns.
MeOH/CHCl3/EtOAc -- Similar to MeOH/DCM/EtOAc. Three solvent system.
(NH3) MeOH/DCM 1-10% (7N NH3 in MeOH)/(DCM)
    [see procedure]
0-20% (10% NH3 in MeOH)/(DCM)
    [see procedure]
4% (7N NH3 in MeOH)/(DCM)   [see procedure]
Good for moving polar, basic compounds. Usually uses commercially purchased NH3 in MeOH (ex. 7N NH3 in MeOH).
(NH4OH) MeOH/DCM 0-5% (10% NH4OH in MeOH)/(DCM)
    [see procedure]
10-45% (90:9:1 DCM/MeOH/NH4OH)/(DCM)
    [see procedure]
100% DCM to 97% DCM, 3% MeOH, 0.1% NH4OH
    [see procedure]
Good for moving polar, basic compounds.
(Et2NH) MeOH/DCM 0-100% (970:27:3 DCM/MeOH/Et2NH)/(DCM)
    [see procedure]
Good for moving polar, basic compounds.
(TEA) MeOH/DCM -- Good for moving polar, basic compounds.
(DIEA) MeOH/DCM 2-4% MeOH/DCM (with 0.1% DIEA)
    [see procedure]
Good for moving polar, basic compounds.
(AcOH) MeOH/DCM -- Good for moving acidic compounds (ex. carboxylic acids).
(HCO2H) MeOH/DCM 2/98/0.1 to 20/80/1 MeOH/DCM/HCO2H
    [see procedure]
Good for moving acidic compounds (ex. carboxylic acids).

EtOH

Solvent System Examples Comments
EtOH/DCM 0-5% EtOH/DCM    [see procedure]
0-10% EtOH/DCM    [see procedure]
Similar to MeOH/DCM.
EtOH/EtOAc 0-45% EtOH/EtOAc    [see procedure] Similar to MeOH/EtOAc.
EtOH/EtOAc/heptane 0-100% (76:24 EtOAc:EtOH)/(heptane)
    [see procedure]
Three solvent system.

acetone

Solvent System Examples Comments
acetone/hexane 30% acetone/hexane    [see procedure] --
acetone/heptane 15-25% acetone/heptane    [see procedure] Similar to acetone/hexane. Heptane is a less toxic alternative for hexane.
acetone/DCM 0-50% acetone/DCM    [see procedure] --

DCM

Solvent System Examples Comments
DCM 100% DCM    [see procedure] As a one component solvent system there is no ability to create a gradient. It still may be useful for easy separations.
DCM/hexane 20% DCM/hexane    [see procedure]
0-30% DCM/hexane    [see procedure]
--
DCM/heptane 90-100% DCM/heptane    [see procedure]
0-20% DCM/heptane    [see procedure]
Similar to DCM/hexane. Heptane is a less toxic alternative for hexane.
DCM/cyclohexane 0-25% DCM/cyclohexane    [see procedure] Cyclohexane (similar to heptane) is a less toxic alternative for hexane.

ether

Solvent System Examples Comments
ether/heptane 10% ether/heptane    [see procedure] Diethyl ether presents flammability concerns.

IPA

Solvent System Examples Comments
(NH4OH) IPA/toluene 1:69:30 NH4OH/toluene/IPA    [see procedure] Not a very common solvent system. The use of NH4OH should help move polar, basic compounds. The UV activity of toluene can complicate matters.