Process for the preparation of 4-bromo-1,8-naphthalic acid anhyd

Details Process for the preparation of 4-bromo-1,8-naphthalic acid anhyd Process for the preparation of 4-bromo-1,8-naphthalic acid anhyd

1976-02-11

1977-07-05

Morgenstern, Norman

Chemistry of carbon compounds

Miscellaneous organic carbon compounds

C-metal

C07D31102

Patent

active

040339866

ABSTRACT:
A novel method for the preparation of 4-bromo-1,8-naphthalic acid anhydride is disclosed. This method is carried out by the bromination, with alkali metal bromide or molecular bromine in the presence of a hypohalite, of a di-alkali metal salt of 1,8-naphthalic acid in aqueous solution at a pH of between 6.5 and 9.5 and at a temperature of between 0.degree. and 30.degree. C. to a di-alkali metal salt of 4-bromo-1,8-naphthalic acid and cyclizing to produce 4-bromo-1,8-naphthalic acid anhydride. This novel direct bromination method produces the desired product in good yields and high purity. 4-Bromo-1,8-naphthalic acid anhydride is a valuable intermediate for the preparation of dyestuffs, pigments and optical brighteners.

REFERENCES:
patent: 3646069 (1972-02-01), Okada et al.
patent: 3850965 (1974-11-01), Williams
patent: 3888885 (1975-06-01), Dencker et al.
Farkas et al., "J.A.C.S.", vol. 71, 1988 (1949).

Affiliated with

Also associated with

Rating

Process for the preparation of 4-bromo-1,8-naphthalic acid anhyd 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 4-bromo-1,8-naphthalic acid anhyd, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the preparation of 4-bromo-1,8-naphthalic acid anhyd will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-577343