112127-50-1Relevant articles and documents
Oxocarbons and Related Compounds; Part 12. A Simple and Efficient Synthesis of 3-Hydroxy-3-cyclobutene-1,2-dione ("Semisquaric Acid"; "Moniliformin") and its Reaction with Amines
Schmidt, Arthur H.,Maibaum, Harry
, p. 134 - 137 (1987)
Starting with squaric acid (1), semisquaric acid (4) has been synthesized in a 54percent overall yield.In contrast to a literature report semisquaric acid (4) reacts with ammonia (5a) and aniline (5b) in the cold to give the ammonium-semisquarates 6a and