Formation and Properties of Some Uretediones

ofmann (Ber., 4, 246. 1871.) found that triethylphosphine served as a catalyst to cause the polymerization of phenyl isocyanate to a dimer which he designated as diphenyl diisocyanate. Staudinger ( Die Ketene , Enke, Stuttgart, 1912, p. 126.) regarded this product as a four atomic ring derivative. It has now been found that triethylphosphine polymerizes a number of substituted phenylisocyanates, such as λ- and β-naphthyl isocyanates, and p-xenyl isocyanate. These products which have more recently been listed as derivatives of uretedione, react with aliphatic amines to produce substituted biurets