Schweizer's reagent in aqueous form
| IUPAC name
Tetraammine copper(II) hydroxide dihydrate
| Other names
|Molar mass||201.71 g/mol|
|Appearance||Deep blue (solution)|
|Solubility|| Reacts with acids|
Insoluble in organic solvents, may break down
|Safety data sheet||None|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Schweizer's reagent (sometimes written as Schweitzer's reagent) is a deep-blue solution of the coordination complex tetraammine copper(II) hydroxide, with the generally accepted formula [Cu(NH3)4(H2O)2](OH)2. This solution can be produced by dissolving copper(II) hydroxide in an excess of ammonia. It is notable for its ability to dissolve cellulose, and a solution of cellulose in Schweizer's reagent can be used to manufacture rayon fiber by injecting it into sulfuric acid solution.
The name Schweizer's reagent is also used for another compound, triphenylvinylphosphonium bromide, though they are very different compounds.
Schweizer's reagent will decompose if heated to give off ammonia.
Schweizer's reagent is a deep-blue solution, with a strong ammonia smell. It can be dried in an ammonia stream, and its crystals are only stable under excess ammonia.
Schweizer's reagent is best made that purchased.
Schweizer's reagent can be made by bubbling ammonia through a copper(II) hydroxide solution. Adding copper metal to a solution of ammonia also yields the complex, though this process takes a long time.
- Produce rayon
Tetraammine copper(II) hydroxide solutions give off ammonia fumes which are irritant and toxic.
Best stored in closed bottles or tubes, and kept away from heat. Dry crystals should be kept in an ammonia atmosphere in closed containers.
Heating the compound causes it to release ammonia and leave behind copper(II) hydroxide or oxide. Do this outside or in a fumehood.
Alternatively, you can add an acid and convert the compound to ammonium and copper salts of the acid. Copper ions can be reduced to metallic copper which can be recycled, while ammonium salts can be either recycled or dumped in trash.