New methods Carboxylation of Grignard Reagents Grignard reagents can react as nucleophiles and attack carbon dioxide. R一X 0=c∠o R-C-0:'Mgx H R-C-OH (alkyl or 盖品RMex aryl halide) This results in magnesium salts of carboxylic acids,and treatment with dilute acid produces a carboxylic acid. The overall transformation is from alkyl halide to a carboxylic acid with an extra carbon atom. E.g. Br Mg,ether MgBr CO2 CO2MgBr H30+ CO2H Ch20 Carboxylic Acids (landscape) Page 15Ch20 Carboxylic Acids (landscape) Page 15 New methods Carboxylation of Grignard Reagents Grignard reagents can react as nucleophiles and attack carbon dioxide. This results in magnesium salts of carboxylic acids, and treatment with dilute acid produces a carboxylic acid. The overall transformation is from alkyl halide to a carboxylic acid with an extra carbon atom. E.g. Br Mg, ether MgBr CO2 -+MgBr CO2 H3O+ CO2H