Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

The registered substance, (R)-(-)-butane-1,3-diol (CAS No. 6290-03-5), is an odourless clear light-yellow liquid at 20 °C and 1013 hPa. Based on structure, surface activity is not expected. Experience in production and handling shows that the registered substance does not react with water. The registered substance is known to be stable in contact with air at room temperature for prolonged periods of time (days). Based on structure, there are no chemical groups present in the molecule which are associated with explosive or oxidising properties. Also, the registered substance does not contain an ionisable functional group.

Data for (R/S)-butane-1,3-diol (CAS No. 107-88-0) is used to address the remaining physical-chemical property data requirements for (R)-(-)-butane-1,3-diol (CAS No. 6290-03-5) in an analogue read-across approach. The basis for this read-across approach is the extreme structural similarity of the source and target substances, in that the source substance is a racemic mixture of a pair of enantiomers, whereas the target substance is solely the R-enantiomer of that source pair. Two compounds that are enantiomers of each other have the same physical properties, except for the direction in which they rotate polarized light and how they interact with different optical isomers of other compounds (ECHA, 2008). On this basis, the physical-chemical property values available for the source substance are directly applicable to the target substance.

Handbook or collections of data values for (R/S)-butane-1,3-diol were referenced for the following endpoints. The melting point of the registered substance is predicted to be <-50 °C and the boiling point is predicted to be 207.5 °C at 101 325 Pa. The relative density is predicted to be ≥1.004 to ≤1.006 g/cm³ at 20 °C. The vapour pressure is predicted to be >8 to <10 Pa at 20 °C.  The water solubility is predicted to be approximately 999 800 mg/L at 25 °C. The flash point is predicted to be 121 °C, which does not meet the criteria for classification according to CLP (EU 1272/2008 as amended) for a flammable liquid. The self-ignition temperature is predicted to be 395 °C. The viscosity is predicted to be > 96 and < 98 mm²/s at 25 °C.

A combination of values from collections of data for (R/S)-butane-1,3-diol and results derived from a valid (Q)SAR models were used to predict the n-octanol-water partition coefficient of the registered substance. The n-octanol-water partition coefficient is predicted to be ≥-0.92 to ≤-0.08.

Additional information