Selected non-quantitative transesterifications were analyzed by
thin-layer chromatography (TLC) on EMD silica gel 60 F254
plates using a 1 : 1 hexanes : dichloromethane solvent system to
assess the presence of acylglycerol starting materials.
Acknowledgements
The work was generously supported by funding from Brown
University, including an R. B. Salomon Award to J.K.S., NSF-
MCB grant 0920713 to J.K.S. provided additional funding. A.M.S.
was supported by a NSF American Competitiveness in Chemistry
post-doctoral fellowship 0936994.
Chemistry
All transesterifications used 35 mmol of the triacylglycerol and 10
mol% of either Sc(OTf)3 or Bi(OTf)3. The reactions were carried
out in the microwave reactor with either 6, 12, or 48 equivalents
of methanol per ester of the triacylglycerol for the indicated
period of time. Upon completion, the reactions were analyzed as
described in the general methods section. Analytical TLC of non-
quantitative reactions revealed only the presence of triacylglycerol
starting materials; no mono- or di-acylglycerols were detected.
All esterifications used 100 mmol of the fatty acid and 1 mol% of
either Sc(OTf)3 or Bi(OTf)3. The reactions were carried out in the
microwave reactor with either 12, 24, or 48 equivalents of methanol
per fatty acid for the indicated period of time. Upon completion,
the reactions were analyzed as described in the general methods
section.
In the case where the esterification and transesterification were
carried out in “one-pot”, 35 mmol of triolein and 85 mmol of
palmitic acid were dissolved in 205 mL of MeOH with 10 mol% (3.5
mmol) of either Sc(OTf)3 or Bi(OTf)3. The reactions were heated
to 150 ◦C for 20 min in the microwave reactor. Upon completion,
the reactions were analyzed as described in the general methods
section.
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