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ChemicalBook CAS DataBase List 2,2-DIBROMO-1-METHYL-CYCLOPROPANECARBOXYLIC ACID
5365-21-9

2,2-DIBROMO-1-METHYL-CYCLOPROPANECARBOXYLIC ACID synthesis

8synthesis methods
-

Yield:5365-21-9 93.6%

Reaction Conditions:

with benzyltriethylammonium bromide;sodium hydroxide at 20; for 4 h;

Steps:

2.1

General procedure: To a 500 ml three-neck round bottom flask equipped with a mechanical stirrer,25.8 g of methacrylic acid (0.3 mol),100 ml of chloroform,0.5 g of triethylbenzylammonium bromide,160 ml of a 30% solution of sodium hydroxide,Followed by stirring at room temperature for 4 hours.Stirring was stopped,Layers are placed.The lower layer is organic phase,The upper water layer,The aqueous phase was added 80 ml of concentrated hydrochloric acid dropwise to pH = 1 with stirring,And then stir for half an hour,Extracted with methylene chloride,The organic phases were combined,Dried, evaporated to remove the solvent,To give 43.7 g of 2,2-dichloro-1-methylcyclopropylcarboxylic acid,The yield was 86.2%Purity & gt; 95%. Instead of chloroform with tribromomethane,Using the same procedure,2,2-dibromo-1-methylcyclopropylcarboxylic acid,The yield was 93.6%Purity & gt; 95%.

References:

CN104447293,2016,B Location in patent:Paragraph 0045; 0046