4-Hydroxybenzaldehyde → 1,2-Ethanediol, 1,2-bis(4-hydroxyphenyl)-

Temperature

15 °C

A solution containing 20.0 grams (0.16 mole) of 4-hydroxybenzaldehyde and 200 milliliters of 1.0 molar aqueous sodium hydroxide was charged to the reservoir. Also charged to the reservoir was a small amount of Union Carbide SAG 470 silicone antifoam agent. The solution was circulated through the cell at a flow rate of about 1500 milliliters per minute. The electrolysis was conducted at a constant current of 5.0 amperes and a temperature of 30° C over a 1.36-hour (4900-second) period. After the electrolysis had been completed, the solution was removed from the apparatus, which was then washed with water. The combined solution and washings were reduced in volume to 100 milliliters by evaporation in vacuo. The remaining solution was acidified to about pH 6.3 by the dropwise addition of dilute (approximately 6 molar) hydrochloric acid and cooled to 15° C in an ice-water bath. The precipitate was collected by suction filtration, washed with cold water, and dried to yield 15.2 grams of 1,2-bis(4-hydroxyphenyl)ethane-1,2-diol.

1. additionwas charged to the reservoir
2. additionAlso charged to the reservoir
3. waita temperature of 30° C over a 1.36-hour (4900-second) period
4. customthe solution was removed from the apparatus, which
5. washwas then washed with water
6. customThe combined solution and washings were reduced in volume to 100 milliliters by evaporation in vacuo
7. additionThe remaining solution was acidified to about pH 6.3 by the dropwise addition
8. additionof dilute (approximately 6 molar) hydrochloric acid
9. filtrationThe precipitate was collected by suction filtration
10. washwashed with cold water
11. customdried

ORD record

ord-1c149b15881e4e1db39ad1e39ab8057a

Source dataset

uspto-grants-1978_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04087336