Yes, N-methylmorpholine and water form a minimum boiling azeotrope consisting of 74.5% N-methylmorpholine and 25.5% water. The boiling point of the azeotrope is 114.5 °C.
Azeotropes are mixtures of two or more liquids that have a constant boiling point and composition over a range of pressures. Azeotropes form when the intermolecular forces between molecules in a mixture are stronger than those in a pure liquid.
The formation of N-methylmorpholine-water azeotrope is because the hydrogen bond between N-methylmorpholine and water molecules is stronger than that of pure N-methyl Hydrogen bonds between morphine or pure water molecules are strong. The stronger hydrogen bonds in the azeotrope prevent the molecules from escaping into the gas phase until the temperature rises to 114.5 °C.
