3,4-Dimethoxy-3-cyclobutene-1,2-dione (Dimethyl squarate) finds it uses in the synthesis of chiral squaramides, highly enantioselective catalyst for the Friedel-Crafts reactions of indoles, 3-(hydroxyamino)-4-methoxy-3-cyclobutene-1,2-dione, squarate derivatives of the O-SP-core antigens, methyl squarate derivative of the Ogawa O-SP-core antigen, o-quinodimethanes, benzocyclobutenes, quinones. It is employed as a starting material in the preparation of o-quinodimethanes, benzocyclobutenes, and quinones.
3,4-Dimethoxy-3-cyclobutene-1,2-dione (Dimethyl squarate) is a cyclobutene derivative. It reacts with hydroxylamine derivatives to afford 3-hydroxyamino-4-methoxy-3-cyclobutene-1,2-diones.