ChemicalBook CAS DataBase List 3-(Trifluoromethoxy)bromobenzene

3-(Trifluoromethoxy)bromobenzene synthesis

5synthesis methods

Product Name:3-(Trifluoromethoxy)bromobenzene
CAS Number:2252-44-0
Molecular formula:C7H4BrF3O
Molecular Weight:241.01

461-82-5

2252-44-0

The general procedure for the synthesis of 3-trifluoromethoxybromobenzene from p-trifluoromethoxyaniline is described below: Example 5 (comparative experiment) Preparation of 1-bromo-3-trifluoromethoxybenzene using bromine (Br2) in acetic acid medium. This was done as follows: 60 g of acetic acid was added to a 100 mL round bottom flask, followed by the slow addition of 30 g of 4-trifluoromethoxyaniline. After cooling the reaction mixture to 0-5 °C, 27 g of bromine was slowly added dropwise. Upon completion of the reaction, the reaction mixture was analyzed by gas chromatography, which showed 20% unreacted 4-trifluoromethoxyaniline, 37% monobrominated derivatives and more than 41% dibrominated derivatives.

1535-75-7 Synthesis

1535-75-7
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$5.00/5g

2252-44-0
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$7.00/5g

Yield:2252-44-0 66.6 %Chromat.

Reaction Conditions:

Stage #1:2-trifluoromethoxy aniline with sulfuric acid at 40 - 45;
Stage #2: with N-Bromosuccinimide in sulfuric acid at 0 - 5; for 1.5 h;Product distribution / selectivity;

Steps:

4
EXAMPLE 4 (COMPARATIVE) Preparation of l-bromo-3-trifluoromethoxybenzene with NBS in concentrated sulphuric acid. 30.3 g of concentrated sulphuric acid (95-98%) are placed in a 100 ml reactor and 10 g of 2-trifluoromethoxyaniline are added, dropwise, as in the previous example at approximately 40-45⁰C. Once a uniform solution has been obtained, it is cooled to 0- 5°C with cryostat. 10.1 g of NBS are metered in portions over a period of 1 hour, then left to complete for a further 30 minutes. The mixture gradually turns yellow and then brown. A gas chromatograph analysis is performed at the end of the reaction:15.3% of 2-trifluoromethoxyaniline, 66.6% of mono-bromo-derivative as per the title, 11.1 % of di-bromo and tri-bromo-derivatives.

References:

MITENI S.P.A. WO2007/107820, 2007, A2 Location in patent:Page/Page column 9

64115-88-4 Synthesis