Diethyl tert-butylmalonate is used in the preparation of enantiomers of 4-tert-butyl-3-isopropyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-sulfide.
Dissolve it in Et2O, wash with aqueous NaHCO3, H2O, dry (MgSO4), filter, evaporate and distil the residue. Identify by hydrolysis to the acid and determine the neutralisation equivalent (theor: 80.0). The acid has m 155-157o effervescence [Hauser et al. J Am Chem Soc 64 2715 1942, Bush & Beauchamp J Am Chem Soc 75 2949 1953]. [Beilstein 2 IV 2027.]
