Sodium Hydroxide → HCID 178437663, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of the compound of part (ii) (40 kg) and water (10 kg) was heated to 90° C. and 4N aqueous sodium hydroxide solution (127 L) added. Heating was continued at 80° C. for 30 minutes and then the mixture was cooled to 25° C. The mixture was washed with toluene (124 L), the aqueous layer separated and dichloromethane (162 L) added thereto. To this mixture was added concentrated hydrochloric acid until pH1 was achieved. The organic layer was separated and the aqueous layer extracted with dichloromethane (162 L). The combined organic layers were treated with activated carbon (Norit-trade mark) (8.8 kg). The solution was filtered and the filtrate treated with concentrated aqueous ammonia solution until pH9 was achieved. The product precipitated as a solid and was collected by filtration (34 kg), m.p. 125–131° C.

Provenance & Evidence