Process for the preparation of 1,5-dihydroxynaphthalene and 1,5-

Details Process for the preparation of 1,5-dihydroxynaphthalene and 1,5- Process for the preparation of 1,5-dihydroxynaphthalene and 1,5-

1989-11-21

1990-11-27

Hollrah, Glennon H.

Organic compounds -- part of the class 532-570 series

Organic compounds

Amino nitrogen containing

C07C20918

Patent

active

049737589

ABSTRACT:
The characteristic of the improved process for the preparation of 1,5-dihydroxynaphthalene and 1,5-diaminonaphthalene is to carry out the alkaline pressure hydrolysis of the disodium salt of naphthalene-1,5-disulphonic acid at temperatures from 270.degree. to 290.degree. C. and under 14 to 20 bar using an excess of sodium hydroxide solution such that the molar ratio NaOH/disodium salt of naphthalenesulphonic acid is at least 12:1. The 1,5-dihydroxynaphthalene which is obtained in this manner, without hazard and in substantially higher purity, is then aminated with ammonia in the presence of ammonium bisulphite to give 1,5-diaminonaphthalene, it being possible to achieve a further increase in the degree of purity of the 1,5-diaminonaphthalene by increasing the molar ratio NH.sub.3 /1,5-dihydroxynaphthalene to at least 6:1.

REFERENCES:
patent: 455442 (1891-07-01), Schmid
patent: 2363819 (1944-11-01), Glahn et al.

Affiliated with

Also associated with

Rating

Process for the preparation of 1,5-dihydroxynaphthalene and 1,5- does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for the preparation of 1,5-dihydroxynaphthalene and 1,5-, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the preparation of 1,5-dihydroxynaphthalene and 1,5- will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1033018