1-methyl-4-piperidyl diphenylglycolate

Boiling point

Administrative data

Endpoint:

boiling point

Data waiving:

study technically not feasible

Justification for data waiving:

the study does not need to be conducted because the substance is a solid which decomposes before boiling

Applicant's summary and conclusion

Conclusions:

The determination of the boiling point of 1-methyl-4-piperidyl diphenylglycolate is technically not feasible because decomposition below boiling point occurs.

Executive summary:

Normally the determination of the endpoint „boiling point“ (e.g. acc. to regulation no. 440/2008/EC method A.2) would be required.

According to regulation no. 1907/2006/EC; Annex VII; 7.3; column 2, the study does not need to be conducted for solids which either melt above 300 °C or decompose before boiling (e.g. auto- oxidation, rearrangement, degradation, decomposition, etc.). In such cases the boiling point under reduced pressure may be estimated or measured.

Method/apparatus:
The distillation method for boiling temperature acc. to A.2; 1.4.3 with a classic “Liebig distillation apparatus (Claisen head, Liebig condensor, vacuum bent adapter, thermometer) was used.

Test material:
Batch 16002353, date of production: 11/11/2009; purity 99.85%; impurities: Benzilc acid < 0.01%; BME 0.05%; unknown constituents 0.01 %.

Distillation test at standard pressure (99.8 kPa; uncorrected):
A distillation at standard pressure of 4.322 g test material is technically not feasible because a complete decomposition below boiling point to a dark-brown, amine-like distillate (1.378 g) and a black-viscous distillation residue occur (bottom temp. approx. 280 – 300 ° C; overhead temp. 120 – 160 ° C). A complete decomposition [ester cleavage to piperidine derivatives (approx. 5 - 10 % 1-methyl-4-hydroxy-piperidine) and benzilic acid (approx. 10 %), followed by decarboxylation to benzophenone (approx.. 80 %); only approx. 5 % of starting material 1-methyl-4-piperidyl diphenylglycolate; additional up to 7 unknown compounds] to the dark-brown distillate was observed (semi-quantitatively by TLC).

Distillation test under reduced pressure at 0.95 – 1 kPa:
The distillation under reduced pressure (0.95 – 1 kPa ) of 3.66 g test material is possible with only a low decomposition at 231 – 235 ° C to a yellow distillate, which crystallized to 2.69 g yellow solid (approx. 70 – 80 % starting material 1-methyl-4-piperidyl diphenylglycolate; approx. 20 – 30 % benzophenone; benzylic acid and 1-methyl-4-hydroxy-piperidine were not observed; semi-quantitatively by TLC).