Amine oxide Amine oxide An amine oxide, also known as amine-"N"-oxide and "N"-oxide, is a chemical compound that contains the functional group RN−O, an N−O coordinate covalent bond with three additional hydrogen and/or hydrocarbon side chains attached to N. Sometimes it is written as RN→O or, wrongly, as RN=O. In the strict sense, the term "amine oxide" applies only to oxides of tertiary amines. Sometimes it is also used for the analogous derivatives of primary and secondary amines. Examples of amine oxides include pyridine-"N"-oxide, a water-soluble crystalline solid with melting point 62–67 °C, and "N"-methylmorpholine "N"-oxide, which is an oxidant. Amine oxides
Dihydrogen bond a protic acid and the borane end is hydridic. The resulting B−HH−N attractions stabilize the molecule as a solid. In contrast, the related substance ethane, HCCH, is a gas with a boiling point 285 °C lower. Because two hydrogen centers are involved, the interaction is termed a dihydrogen bond. Formation of a dihydrogen bond is assumed to precede formation of H from the reaction of a hydride and a protic acid. A very short dihydrogen bond is observed in NaBH·2HO with H−H contacts of 1.79, 1.86, and 1.94 Å. Protonation of transition metal hydride complexes is generally thought to occur