abstract |
A new process is described for the preparation of oxalic acid esters and amides of general formula (I) Z- @-@-Z<1> (I) wherein Z designates an -OR or -NR<1>R<2> group, wherein R represents substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aryl, or aryl-alkyl, R<1> is hydrogen or substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aryl, or aryl-alkyl, R<2> represents substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aryl, or aryl-alkyl, or R<1> and R<2> taken together with the adjacent nitrogen atom represent a saturated 5-, 6-, 7-, or 8-membered heterocyclic ring, which may contain an additional heteroatom selected from -O-, -S-, and -N(H, Alkyl)-, and optionally bear one or more alkyl or alkenyl substituents, and Z<1> designates an -OR or -NR<1>R<2> group, wherein R, R<1>, and R<2> are as defined before, or a group -NHCOCH3, which comprises the base-catalysed reaction of diacetyloxamide with an alcohol ROH or/and an amine HNR<1>R<2>. The compounds of formula (I) have many industrial utilities, mainly as intermediates and stabilizers in the polymer field. |