Thionation is a chemical process for substitution of an oxygen atom of carbonyl group with a sulphur atom. Our thionation technology and reagent is easy to use, environmentally friendly, selective and using less energy than the conventional alternative.  

Application areas

Thionation is used in many chemistry related industries, such as pharmaceuticals. In material sciences thionation is used for production of new materials and devices. Thionation is useful synthetic method in heterocyclic chemistry including production of dyes and pigments. Some fragnances used in perfume production require thionation as well.


Pharmaceutical Industry is the major player in consumption of thionation reagents. Thionation is used in synthesis of valuable synthons for drug manufacturing, synthesis of heterocyclic compounds and reactive intermediates. Very interesting and developing area is drugs containing thiocarbonyl fragment including photosensitive drugs (photosensitizers).

Material science

In Material Sciences thionation allow to improve considerably photoelectronic properties of organic materials used for modern transistors, solar cells, batteries and sensors. Polymeric materials with very interesting new properties can be obtained with the help of thionation. Amount of publication concerning thionated materials is rising exponentially during last 15 years.

History of thionation technology

Phosphorus sulfude was prepared for the first time by one of the fathers of organic chemistry Jakob Berzelius in 1843 and very soon was used for preparation of thioketones, thioamides and in many other types of thionation reactions. Thionation reagent was named after Berzelius and it was shown that compound exist in the form of polycyclic neutral molecule P4S10. Berzelius reagent has some disadvantages for organic synthesis due to its heterogeneous composition and bad solubility in organic solvents and after approximately a century in 1976 new derivatives of phosphorus decasulfide were discovered. Reaction of P4S10 with activated benzenes (anisol for example) forms 4-member ring of phosphorus and sulfur atoms with aryl substituents. Compound obtained was introduced as novel thionation reagent by another Swedish chemist Sven-Olov Lawesson. Lawesson’s reagent (LR) has better solubility and distinctive structure. Nowadays it substituted most of the application of P4S10 in organic synthesis for thionation of carbonyl compounds.

Novel thionation reagent was introduced by yet another Swedish scientist Prof. Jan Bergman, founder of Vironova Medical in 2011. Jan Bergman’s reagent (JBR) is also derivative of P4S10 and has acyclic betaine structure with relatively good solubility in organic sovents, good termal stability and better selectivity of thionation in comparison with Lawesons reagent. Besides it has considerable environmental benefits especially for industrial applications.

There are number of other synthetic approaches for preparation of thionated compounds and some other thionation reagent like sulfur, thiourea or sodium bisulfite, but thionation process using phosphorus sulfide and it’s derivatives like LR is still predominant in chemical synthesis and industry.

Our products

JBR – Solid reagent

Pyridine and Phosphorus Pentasulfide (P4S10) react readily to form the powder solid reagent. Your choice of solvent can be used. (e.g. sulfolane or acetonitrile)

Chemical name : Pentathiodiphosphorus(V) acid-P,P′-bis(pyridinium betaine)
CAS No: 16610-51-8 
Mw: 380.5, C10H10N2P2S5
X-Ray: CSD Entry UYUCUN 789666
Patent: WO2012104415

Excellent for thionation of amides and ketones, 0.25 – 0.33 equivalents of reagent can be used for full thionation of one C=O group of substrate. Easy work up procedures – all JBR derivatives (pyridine and thiophosphonic acid) are water soluble. Alcohols can be used for workup. Often no chromatography required due to high purity of the crude product.

Clean reaction, good thermal stability up to 180ºC, compared to Lawesson’s reagent that slowly decomposes >110ºC. Odorless, stable reagent in anhydrous conditions, good selectivity

ThioTORJBR in Sulfolane

Pyridine, Phosphorus Pentasulfide (P4S10) and sulfolane react readily to form the liquid reagent. Easy to use and store. Quality tested over time.

Yellow to orange solution, containing up to 0,3M (9,5%) of JBR in sulfolan. Stable formulation of JBR (tested stability up to 1,5 years without any loss of thionation activity) when kept under inert gas in sealed bottle at ambient temperatures. Ready to use reagent for thionation with or without addition of another solvent.

Thionation process 

Development of effective synthetic procedures for thionation of appropriate carbonyl substrates using JBR or ThioTOR

Custom synthesis of thionated compounds and heterocyclizations using thionation procedure.

Use our technology commercially with an in-license agreement. 

Our thionation reagent is available for purchasing upon request. Smaller batches are produced in-house, and larger batches by Recipharm, Uppsala, Sweden.

For orders or a free test sample of our thionation reagent, please send us an email.

Advantages of JBR

  • Eco-friendly low energy consumption and cost effective production of the reagent.
  • Higher effectiveness of thionation – transfer up to 4 sulfur atoms for 1 equivalent of reagent.
  • Better selectivity of thionation, that improves purity and yield of final thionated products. Selectivity allows to use thionation for more complex substrates.
  • Stability at high temperatures (up to 1850C), that profitable for thionation of polymeric materials and substrates that require prolong heating for complete thionation.
  • Easy work-up procedures, due to water soluble reaction byproducts, that simplifies product purification.
  • JBR can be used in the form of ThioTOR that can simplify preparation, storage and the use of thionation reagent.
  • Developed analytical procedures for quality control of the reagent.

In general JBR can thionate limited set of substrates – amides, lactams and ketones, in comparison with Lawesson’s reagent, but that anyway covers more than 50% of its industrial applications.

Environmental benefits and cost savings 

  • Eco -friendly
  • Less toxic waste
  • Fast and mild process
  • Lower energy consumption
  • Higher yield
  • Cheaper starting materials