Phenyl chloroformate

Hydrolysis

Administrative data

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Predates implementation of GLP and/or development of study guidelines, acceptable with restrictions.

Data source

Reference

Reference Type:

publication

Title:

Kinetics of the hydrolysis of acyl chlorides in pure water

Author:

Queen A.

Year:

1967

Bibliographic source:

Canadian Journals of Chemistry, Vol. 45, 1619-1629, (1967)

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Phenyl chloroformate

EC Number:

217-547-8

EC Name:

Phenyl chloroformate

Cas Number:

1885-14-9

Molecular formula:

C7H5ClO2

IUPAC Name:

phenyl chloroformate

Details on test material:

- Name of test material: Phenyl chloroformate
- Source: Aldrich chemical Company
- Test compound was fractionated before use.
- Purities were checked by titrating the acid or chloride ions formed after shaking with a large excess of water for 20 half-lives.

Study design

Details on test conditions:

Solvent: A careful investigation of the solvolyses in pure water has been carried out over wide ranges of temperature. There were several reasons for choosing this solvent, not the least important being the great accuracy with which rates may be determined and elimination of the possibility of nucleophilic intervention by the organic components of mixed solvents.

Materials: Conductivity water was prepared by distilling water first from a weakly alkaline solution of potassium permanganate, then from sodium bisulfate, and finally alone from an all-glass apparatus.

Measurement of Rates: All experiments were carried out in conductance cells immersed in a constant temperature bath which was steady to ± 0.003 °C or better. Temperatures were measured with a Leeds and Northrup platinum resistance thermometer attached to a Leeds and Northrup 8067 G-1 Mueller bridge, which was maintained at 30 ± 0.1 °C and had been calibrated against a standard 10.01 Ω resistor. The operation of the thermometer and bridge was checked against Dr. R. E. Robertson's more accurate apparatus before use. The kinetic data were obtained using a conductance method and employing the relation log (1/R2 - 1/R1) = kt - C. The reaction mixtures were always degassed before the experiments were carried out. In the cases of Phenyl chloroformate the very fast rates were measured using a modification of the method described by Moelwyn-Hughes, Robertson, and Sugamori (J. Chem. Soc. 1965) in which the conductance bridge setting, the bridge balance, and the time indicated on a digital clock were recorded by means of a motor driven 35 mm camera.

Results and discussion

Details on hydrolysis and appearance of transformation product(s):

See table 1 in any other information on results incl. tables

Other kinetic parameters:

- See table 2 in any other information on results incl. tables
- Relative rate of hydrolysis of phenyl chloroformate in water at 25°C is 36.5
- The rate of hydrolysis of phenyl chloroformate in deuterium oxide at 7.534°C is 15.71E4 x kD2O(s^-1) and 0.56 kD2O/kH2O

Any other information on results incl. tables

Table 1: Rate of hydrolysis of phenyl chloroformate in water. (Average values of several independent experiments at each temperature and calculated values.)

Temp. (°C)	10³ x k(obs.) (s^-1)	10³ x k(calcd.) (s^-1)	n*
0.396	1.329 ± 0.002	1.329	3
2.271	1.615 ± 0.001	1.617	3
4.771	2.092 ± 0.006	2.088	4
7.534	2.744 ± 0.006	2.750	3
9.877	3.461 ± 0.002	3.455	3
12.193	4.298 ± 0.003	4.306	3
14.725	5.456 ± 0.001	5.448	3
17.431	6.956 ± 0.013	6.961	3
19.601	8.437 ± 0.014	8.436	3

*n is the number of independent kinetic experiments.