Di-tert-butyl dicarbonate,an example of hitherto unknown class of compounds,has been prepared only by the present procedure.
The corresponding sulfur compound, tert-C4H9SCO2CO2COS-tert-C4H9, also belongs to a new class of compounds and has been prepared by a similar procedure in comparable yields.Both tricarbonates are smoothly converted by basic catalysts into the corresponding dicarbonates (sometimes called pyrocarbonates); kinetic studies and differences in thermal decomposition of both tricarbonates have been reported, as well as other reactions of these materials.The amine-catalyzed decomposition of the tricarbonates to dicarbonates is believed to involve initial nucleophilic attack by the amine at the center carbonyl group of the tricarbonate.Di-tert-butyl dicarbonate had been obtained previously in 5% yield; no study of its properties was reported.
The di-tert-butyl dicarbonate and its sulfur analog have been shown to react with amino acids and their derivatives to form the corresponding N-tert-butoxycarbonyl (t-BOC) and N-tert-butylthiocarbonyl derivatives,which are valuable protecting groups for amino functions. The dicarbonates described in the present synthesis are very mild reagents for the preparation of t-BOC and N-tert-butylthiocarbonyl derivatives, and may have application in selective reactions with enzymes, nucleic acids and their component nucleotides and nucleosides. Diethyl dicarbonate has been extensively studied in reactions of this type.