Amidogen

The amino radical, •NH2, also known as the aminyl radical or azanyl radical, is the neutral form of the azanide ion (NH−2). Aminyl are highly reactive and consequently short lived like most radicals; however, they form an important part of nitrogen chemistry. In sufficiently high concentration, amino radicals dimerise to form hydrazine. While NH2 as a functional group is common in nature, forming a part of many compounds (e.g. the phenethylamines), the radical cannot be isolated in its free form. The amino radical, •NH2, also known as the aminyl radical or azanyl radical, is the neutral form of the azanide ion (NH−2). Aminyl are highly reactive and consequently short lived like most radicals; however, they form an important part of nitrogen chemistry. In sufficiently high concentration, amino radicals dimerise to form hydrazine. While NH2 as a functional group is common in nature, forming a part of many compounds (e.g. the phenethylamines), the radical cannot be isolated in its free form. Historically, it is generally accepted that the first free radical was identified by Moses Gomberg in 1900; this radical was triphenylmethyl radical. While in general the use of free radicals in organic transformations is difficult to control, organic syntheses with free radicals began in 1937 with Heyes and Waters. After 1940, deeper insights into the formation, structure and reactions of free radicals showed how to control these reactive species in chemical reactions. However, in the 1970s, Lamb and Julia witnessed the beginning of new synthetic methodologies involving free radicals. Nowadays, free radicals are widely used in synthetic reactions.