Tetrahydroxy-1,4-benzoquinone bisoxalate is a chemical compound, an oxide of carbon with formula . Its molecule consists of a 1,4-benzoquinone core with the four hydrogen atoms replaced by two oxalate groups. It can be seen as a fourfold ester of tetrahydroxy-1,4-benzoquinone and oxalic acid.
The compound was first described by H. S. Verter, H. Porter, and R. Dominic in 1968. It was obtained by reacting tetrahydroxy-1,4-benzoquinone with oxalyl chloride in tetrahydrofuran. It is a yellow solid that can be crystallized as a tetrahydrofuran solvate, but could not be prepared in pure form.[1]