Sulfinamide is a

functional group In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest ...

organosulfur chemistry Organosulfur compounds are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature abounds with organosulfur compounds—sulfur ...

with the structural formula RS(O)NR'₂ (where R and R' are organic substituents). This functionality is composed of a

sulfur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

(S–C) and sulfur-

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...

(S–N)

single bond In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond. When shared, each of th ...

s, as well as a sulfur-

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

double bond In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist betw ...

(S=O), resulting in a

tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...

sulfur centre (in resonance with its

zwitterion In chemistry, a zwitterion ( ; ), also called an inner salt or dipolar ion, is a molecule that contains an equal number of positively- and negatively-charged functional groups. : With amino acids, for example, in solution a chemical equilibrium wil ...

ic form). As a non-bonding

electron pair In chemistry, an electron pair or Lewis pair consists of two electrons that occupy the same molecular orbital but have opposite spins. Gilbert N. Lewis introduced the concepts of both the electron pair and the covalent bond in a landmark paper he ...

is also present on the sulfur, these compounds are also chiral. They are sometimes referred to as ''S''-

chiral Chirality is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable from ...

sulfinamides. Sulfinamides are

amide In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent organic groups or hydrogen atoms. The amide group is called a peptide bond when it is ...

s of

sulfinic acid Sulfinic acids are oxoacids of sulfur with the structure RSO(OH). In these organosulfur compounds, sulfur is pyramidal. Structure and properties Sulfinic acids RSO2H are about 1000x more acidic than the corresponding carboxylic acid RCO2H. Su ...

(RS(O)OH). ZIJGUW

Structure

Sulfinamides do not undergo inversion. They can therefore be synthesised and/or isolated in enantiopure forms. This has led to their use as chiral

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...

equivalents and more broadly as chiral auxiliaries.

Synthesis

Sulfinamides are traditionally produced by the reaction of

sulfinyl chloride Sulfinyl halide have the general formula R−S(O)−X, where X is a halogen. They are intermediate in oxidation level between sulfenyl halides, R−S−X, and sulfonyl halides, R−SO2−X. The best known examples are sulfinyl chlorides, thermol ...

s with primary or secondary amines. They also arise by the addition of

Grignard reagent A Grignard reagent or Grignard compound is a chemical compound with the general formula , where X is a halogen and R is an organic group, normally an alkyl or aryl. Two typical examples are methylmagnesium chloride and phenylmagnesium bromide ...

s to sulfinylamines, followed by protonation: :RMgX + R'N=S=O → RS(O)(NR'MgX) :RS(O)(NR'MgX) + H₂O → RS(O)(NR'H) + "MgX(OH)" Yet another route entails peracid-oxidation of sulfenylphthalimides, which gives sulfinylphthalimides.

Examples

A common sulfinamide is ''tert''-butanesulfinamide (Ellman's sulfinamide), ''p''-toluenesulfinamide (Davis' sulfinamide), and 2,4,6-trimethylbenzenesulfinamide. Sulfinamides arise in nature by the addition of

nitroxyl Nitroxyl (common name) or azanone (IUPAC name) is the chemical compound HNO. It is well known in the gas phase. Nitroxyl can be formed as a short-lived intermediate in the solution phase. The conjugate base, NO−, nitroxide anion, is the redox re ...

(HNO) to

thiol In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl gro ...

s: :RSH + HNO → RS(O)NH₂

References

Amides Functional groups {{organic-chem-stub