DIEA Choice for Peptide Synthesis

  • We recently purchased some of Aldrich’s best DIEA and found that there was no detectable AcOH in it. See attached. We have now tested the brands and grades below and have found the following:
  • AlfaAesar, Cat# A11801, 2.5L, $376.00, “99% purity”, contained about 0.03% AcOH by GCMS
  • Aldrich, Cat# D125806, 2.5L, $535.00, “>99% purity”, contained about 0.02% AcOH by GCMS
  • Aldrich, Cat # 496219, 2.0L, $644.00, “99.5% biotech. grade”, not tested by us
  • Aldrich, Cat # 387649, 1L, $425.00, “purified by redistillation, 99.5%”, no detectable AcOH by GCMS
  • For the relatively insignificant $0.10/ml extra cost of Aldrich 387649 vs. Aldrich 496219, we did not bother testing Aldrich 496219 yet.
  • We used the Aldrich 387649 in a synthesis last night and the results showed no acetylated, terminated products. My recommendation is to use this product.
  • Experiment was done by  Jay Lev at Laboratory of Prof. Richard D. Dimarchi