Bisphenol A → Methyl Bromide

HRID 1608733Notes

Reaction equation

HRID 1608733 reaction equation
[OH:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([C:11]2[CH:16]=[CH:15][C:14]([OH:17])=[CH:13][CH:12]=2)([CH3:10])[CH3:9])=[CH:4][CH:3]=1.BrBr.[Br:20][C:21]1C(O)=C(Br)C(Br)=C(C(C2C=CC(O)=CC=2)(C)C)C=1Br>CO>[CH3:21][Br:20].[OH:1][C:2]1[CH:3]=[CH:4][C:5]([C:8]([C:11]2[CH:12]=[CH:13][C:14]([OH:17])=[CH:15][CH:16]=2)([CH3:10])[CH3:9])=[CH:6][CH:7]=1

Participants

6

Reactant 3

HCID 6623Bisphenol A4×HCID 24408BromineHCID 542409822,3,5,6-Tetrabromo-4-[2-(4-hydroxyphenyl)propan-2-yl]phenol

Product 2

HCID 6323Methyl BromideHCID 6623Bisphenol A

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

In a reaction vessel was placed 1000 parts methanol and 230 parts of bisphenol-A. Bromine was fed over a 90 minute period in an amount between 0.99 and 0.995 times the theoretical amount needed to covert the bisphenol-A to tetrabromobisphenol-A. The method for brominating the bisphenol-A was generally in accordance with the method disclosed in U.S. Pat. No. 4,783,556, incorporated herein by references as is fully set forth. The reaction mixture was held at reflux during the bisphenol-A bromination sequence and methyl bromide was produced during the entire bisphenol-A bromination process. After the bromine addition was completed, the system was held at reflux for 30 minutes to produce additional methyl bromide which was distilled out of the reaction mixture. Heating was stopped and 400 parts of water was added over a 30 minute period to precipitate the TBBPA and to halt methyl bromide production. The reaction medium was then allowed to cool to 30°-40° C. and TBBPA product was removed by centrifugation and wash with 5 parts of methanol and 5 parts of water. The centrate was neutralized with NaOH to a pH of 12-13 and then distilled to remove methanol. The resulting 870 parts of distillation column bottoms contained 1.7 weight percent sodium salts of tetrabromobisphenol-A, 1.7 weight percent sodium salts of tribromobisphenol-A, 0.2 weight percent sodium salts of tribromophenol, 0.2 weight percent sodium salts of other brominated phenolics, 0.5 weight percent NaOH, 0.3 parts of methanol, and about 12 weight percent NaBr.

Workup

  1. customIn a reaction vessel was placed

Sources & evidence

ORD record
ord-05595f372ded4f7483516295f6718688
Source dataset
uspto-grants-1995_03
Patent number
US05395994

Reaction notes

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