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Overview of Dry Column Vacuum Chromatography

Mar 4, 2025

Lecture Notes on DCVC (Dry Column Vacuum Chromatography)

Introduction

  • Presenter: Daniel S. Peterson, Associate Professor in Medicinal Chemistry, University of Copenhagen
  • Topic: Introduction to dry column vacuum chromatography (DCVC)
  • Objective: Basic tutorial on equipment needed, column setup, and running DCVC
  • Further Resources: Links to useful websites and publications provided at the end

What is DCVC?

  • Definition: Silica-based column chromatography technique
  • Purpose: Complements flash column chromatography

Advantages of DCVC Over Flash Column Chromatography

  1. Vacuum-driven Technique
    • Easier to work with than pressure in labs
  2. Equipment Availability
    • Basic equipment available in well-equipped labs
  3. Resource Efficient
    • Uses less silica and solvent
  4. Speed
    • Faster than flash column chromatography
  5. Scalability
    • Easily scales for large-scale purification (e.g., up to 200g purifications)

Disadvantages of DCVC

  1. Small-Scale Inefficiency
    • Less effective for small-scale (e.g., <50mg) purifications
  2. Volatile Compounds
    • Not suitable due to vacuum use
  3. Low Boiling Solvents
    • Difficult with solvents like dichloromethane, acetone, ether

Equipment for DCVC

  • Columns: Tall sintered glass funnel, 7-10 cm height
  • Packing Tools: Plastic rods, bent-tip spatula
  • Receiver Setup: Separatory funnel, vacuum adapter, three-way tap
  • Sophisticated Setup: Custom-made receivers, integrated vacuum adapter
  • Vacuum Source: Soft vacuum, e.g., water aspirator, diaphragm pump
  • Silica Gel: Particle size 15-40 µm recommended

Setting Up DCVC

  1. Column Preparation
    • Use of rubber bung and clamps for stability
    • Importance of soft vacuum application
  2. Column Packing
    • Aim for 5 cm tall packed silica
    • Use plastic tools for tapping and packing
  3. Sample Loading
    • Recommended dry loading using Celite
    • Avoid wet loading

Running DCVC

  • Gradient Elution
    • Use gradient instead of isocratic elution
    • Example: Ethyl acetate:heptane gradient
  • Fraction Collection
    • Aim for 20 ml fractions
  • Efficiency
    • Typically takes 2 hours for complete process

Practical Tips

  • Safety: Use of lab coat, gloves, fume hood
  • Fraction Handling: Do not discard initial fractions immediately
  • Vacuum Adjustments: Essential to have a three-way tap

Additional Resources

  • History and Publications: Original technique by Lawrence Howard
  • Recommended Reading: Paper by Daniel S. Peterson
  • Online Resources: Blog "Curly Arrow" for expert tips and discussions

Conclusion

  • Encouragement to adopt DCVC
  • Available resources for learning and troubleshooting

Note: These notes are a summarized version of the lecture and are intended for educational purposes. Always consult the full resources for detailed procedures and safety guidelines.

Full transcript