Polish version

Dialkyldimethylammonium mandelates

Dialkyldimethylammonium mandelates can occur in the form of a racemate (R,S) or optically active isomers (S)-(+) or (R)-(-). These compounds contain an expanded ammonium cation and a mandelate anion, biocidally active against microorganisms. For instance (R,S) benzalkonium mandelate is most effective against the following microorganisms: Micrococcus luteus, Staphylococcus epidermidis, Staphylococcus aureus, Moraxella catarhalis, Enterococcus faecium, Escherichia coli, Proteus vulgaris, Pseudomonas aureginosa, Serratia marcescens and two fungi: Candida albicans and Rhodotorula rubra.

Dialkyldimethylammonium mandelates belong to the group of surface active cationic compounds and display also electrostatic properties.

These compounds can be constituents of:

  • biocidal preparations,
  • disinfecting/washing preparations.

Didecyldimethylammonium mandelate


Domiphen mandelate


Benzalkonium mandelate


n = 9 60 %

n = 11 40 %

Dialkyldimethylammonium mandelates are thick, waxy compounds, soluble in water, methanol, methylene chloride and acetone, with decomposition temperature > 180 °C.

A brief description of the process

Dialkyldimethylammonium mandelates are obtained in a reaction between dialkyldimethylammonium chloride (bromide) with a potassium salt of mandelic acid [or (R)-(-) – mandelic acid or (S)-(+) – mandelic acid] in aqueous environment at temperature 60 °C. The product is separated by vacuum distilling off water, dissolving in organic solvent, precipitating and filtering off the by-product – potassium chloride and then concentrating the ooze. In order to remove water, additional drying of the product in elevated temperature and under reduced pressure takes place.

Advantages of the technology offered

The technology is simple, low-waste and substrates are cheap. The environment of the reaction is water and the by-product is potassium chlorine.

The reaction yield is high.

The technology to synthesize these compounds has been awarded with a silver medal at PALEXPO Exhibition (Geneva, 2010).


The apparatus set comprises a glass reactor with bottom draining valve, equipped with a high-speed mechanical stirrer, a thermometer and a dephlegmator, which can be exchanged for a distillation set and a heating-cooling jacket, allowing to heat up and cool down the contents.

Auxiliary equipment comprises:

  • thermostat,
  • membrane vacuum pump,
  • vacuum evaporator (to distillate off water from the post-reaction mixture and for final drying of the product).

Advancement of proceedings

There has been compiled documentation concerning physicochemical properties and analytic methods have been developed. No acute toxicity studies have been performed.


pat. PL 213 547 (2012) „New ammonium ionic liquids, a method to obtain them and their application”

Market competitiveness

New ionic liquids are novel compounds with fungicidal and bactericidal properties. Due to their big efficiency, obtaining the desired effect requires only small concentration of these compounds in preparations.

Type of expected cooperation

Cooperation in compiling registration documentation, deployment and launching production of the preparation.


Anna Wiśniewska, M.Sc., Chem. Eng.

phone: + 48 22 568 21 93