Thiophosphoryl chloride
Encyclopedia
Thiophosphoryl chloride is an inorganic compound
with the formula
PSCl3.
Thiophosphoryl chloride, PSCl3, is a fuming, colorless liquid with a pungent odor. It is synthesized from phosphorus chloride
and used to thiophosphorylate organic compounds, such as to produce insecticide
s.
. The most common and practical synthesis, hence used in industrial manufacturing, is directly reacting phosphorus trichloride
with excess sulfur at 180 °C.
Using this method, yields can be very high after purification by distillation. Catalysts can further the reaction at lower temperatures, but are not necessary.
Alternatively, the reaction of phosphorus pentasulfide and phosphorus pentachloride also affords thiophosporyl chloride in yields around 70%.
, carbon tetrachloride
, chloroform
, and carbon disulfide
. However, it hydrolyzes rapidly in basic or hydroxylic solutions, such as alcohols and amines, to produce thiophosphate
s.
PSCl3 is used to thiophosphorylate, or add P=S, organic compounds. This conversion is widely applicable for amines and alcohols, as well as amino alcohols, diols, and diamines. Industrially, PSCl3 is primarily used to produce insecticides, like parathion
.
PSCl3 reacts with tertiary amides to generate thioamides. For example:
Inorganic compound
Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...
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....
PSCl3.
Thiophosphoryl chloride, PSCl3, is a fuming, colorless liquid with a pungent odor. It is synthesized from phosphorus chloride
Phosphorus chloride
Phosphorus chloride may refer to either of the following:*Phosphorus trichloride, PCl3*Phosphorus pentachloride, PCl5See phosphorus halides for a complete list of phosphorus halides....
and used to thiophosphorylate organic compounds, such as to produce insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
s.
Synthesis
Thiophosporyl chloride can be generated by several reactions starting from phosphorus trichloridePhosphorus trichloride
Phosphorus trichloride is a chemical compound of phosphorus and chlorine, having chemical formula PCl3. Its shape is trigonal pyramidal. It is the most important of the three phosphorus chlorides. It is an important industrial chemical, being used for the manufacture of organophosphorus compounds...
. The most common and practical synthesis, hence used in industrial manufacturing, is directly reacting phosphorus trichloride
Phosphorus trichloride
Phosphorus trichloride is a chemical compound of phosphorus and chlorine, having chemical formula PCl3. Its shape is trigonal pyramidal. It is the most important of the three phosphorus chlorides. It is an important industrial chemical, being used for the manufacture of organophosphorus compounds...
with excess sulfur at 180 °C.
- PCl3 + S → PSCl3
Using this method, yields can be very high after purification by distillation. Catalysts can further the reaction at lower temperatures, but are not necessary.
Alternatively, the reaction of phosphorus pentasulfide and phosphorus pentachloride also affords thiophosporyl chloride in yields around 70%.
- 3 PCl5 + P2S5 → 5 PSCl3
Reactions
PSCl3 is soluble in benzeneBenzene
Benzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....
, carbon tetrachloride
Carbon tetrachloride
Carbon tetrachloride, also known by many other names is the organic compound with the formula CCl4. It was formerly widely used in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent...
, chloroform
Chloroform
Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous...
, and carbon disulfide
Carbon disulfide
Carbon disulfide is a colorless volatile liquid with the formula CS2. The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non-polar solvent...
. However, it hydrolyzes rapidly in basic or hydroxylic solutions, such as alcohols and amines, to produce thiophosphate
Thiophosphate
A thiophosphate is a family of compounds and anions with the general chemical formula PS4-xOx3- . The state of protonation is usually not specified. They could be bound to as many as three protons for the neutral H3PS4-xOx species. Two protons correspond to the related monoanions, and one...
s.
- PSCl3 + 4 H2O → H3PO4 + H2S + 3 HCl
- PSCl3 + H2O → HOP(S)Cl2 + HCl
PSCl3 is used to thiophosphorylate, or add P=S, organic compounds. This conversion is widely applicable for amines and alcohols, as well as amino alcohols, diols, and diamines. Industrially, PSCl3 is primarily used to produce insecticides, like parathion
Parathion
Parathion, also called parathion-ethyl or diethyl parathion, is an organophosphate compound. It is a potent insecticide and acaricide. It was originally developed by IG Farben in the 1940s. It is highly toxic to non-target organisms, including humans. Its use is banned or restricted in many...
.
- PSCl3 + 2 C2H5OH → (C2H5O)2PSCl + 2 HCl2PSCl + NaOC6H4NO2 → (C2H5O)2PSOC6H4NO2 + NaCl
PSCl3 reacts with tertiary amides to generate thioamides. For example:
- C6H5C(O)N(CH3)2 + PSCl3 → C6H5C(S)N(CH3)2 + POCl3