Hexafluoroacetone is a chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 with the formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 CF₃-CO-CF₃. It is structurally similar to acetone

Acetone

Acetone is the organic compound with the formula 2CO, a colorless, mobile, flammable liquid, the simplest example of the ketones.Acetone is miscible with water and serves as an important solvent in its own right, typically as the solvent of choice for cleaning purposes in the laboratory...

, however its reactivity is markedly different. It comes in the form of a colourless, hygroscopic, nonflammable, highly reactive gas characterized by a musty odour. The most common form of this substance is hexafluoroacetone sesquihydrate (1.5 H₂O), which is a gem-diol.

Synthesis and reactions

(CF₃)₂CO is prepared in a two step process from perfluoropropene. In the first step KF catalyzes the reaction of the alkene with elemental sulfur to give the 1,3-dithete [(CF₃)₂CS]₂. This species is then oxidized by iodate to give (CF₃)₂CO.

Uses

Hexafluoroacetone is mostly employed in organic synthesis

Organic synthesis

Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic molecules can often contain a higher level of complexity compared to purely inorganic compounds, so the synthesis of organic compounds has...

, but it is also the main chemical intermediate used in the production of hexafluoroisopropanol

Hexafluoro-2-propanol

Hexafluoroisopropanol, commonly abbreviated HFIP, is the organic compound with the formula 2CHOH. This fluorinated alcohol finds use as solvent and synthetic intermediate. It appears as a colorless, volatile liquid that is characterized by a strong, pungent odor...

, as well as polymethyl methacrylates and polyester

Polyester

Polyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate...

s for textile coating. Hexafluoroacetone can be employed as a solvent for acetal resins, polyamide

Polyamide

A polyamide is a polymer containing monomers of amides joined by peptide bonds. They can occur both naturally and artificially, examples being proteins, such as wool and silk, and can be made artificially through step-growth polymerization or solid-phase synthesis, examples being nylons, aramids,...

s, polyglycolide

Polyglycolide

Polyglycolide or Polyglycolic acid is a biodegradable, thermoplastic polymer and the simplest linear, aliphatic polyester. It can be prepared starting from glycolic acid by means of polycondensation or ring-opening polymerization. PGA has been known since 1954 as a tough fiber-forming polymer...

, polyacetals, and polyols or as a polymer

Polymer

A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

 adhesive.

Reactivity

Hexafluoroacetone is a reactive substance, acting primarily as an electrophile

Electrophile

In general electrophiles are positively charged species that are attracted to an electron rich centre. In chemistry, an electrophile is a reagent attracted to electrons that participates in a chemical reaction by accepting an electron pair in order to bond to a nucleophile...

. In water hexafluoroacetone is highly reactive as its equilibrium

Chemical equilibrium

In a chemical reaction, chemical equilibrium is the state in which the concentrations of the reactants and products have not yet changed with time. It occurs only in reversible reactions, and not in irreversible reactions. Usually, this state results when the forward reaction proceeds at the same...

 sharply favors (~10⁶) forming a gem

Geminal

In chemistry, the term geminal refers to the relationship between two functional groups that are attached to the same atom...

-diol

Diol

A diol or glycol is a chemical compound containing two hydroxyl groups A geminal diol has two hydroxyl groups bonded to the same atom...

 hydrate

Hydrate

Hydrate is a term used in inorganic chemistry and organic chemistry to indicate that a substance contains water. The chemical state of the water varies widely between hydrates, some of which were so labeled before their chemical structure was understood....

, unlike the identical unfavorable equilibrium with acetone (10^-3). This makes the equilibria of two chemicals differ by about a billion regarding this addition of water. Hexafluoroacetone-hydrates are acidic and react with most metals to generate hydrogen

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

. Hexafluoroacetone violently reacts in the presence of alkali. Related to its tendency to hydrate, (CF₃)₂CO adds ammonia

Ammonia

Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

 to give (CF₃)₂C(OH)(NH₂) which can be dehydrated with phosphoryl chloride

Phosphoryl chloride

Phosphoryl chloride is a colourless liquid with the formula 3. It hydrolyses in moist air to phosphoric acid to release choking fumes of hydrogen chloride. It is manufactured industrially on a large scale from phosphorus trichloride and oxygen or phosphorus pentoxide...

to give (CF₃)₂CNH.