Acid Halides from Carboxylic Acids

Synthesis of Acid Halides SOCl2 = thionyl chloride PCl5 can also be used

Problems Give the major product for the following reaction: Draw the products you would get from reacting the following molecule with PCl5. What product would you obtain from reacting it with PBr3?

Anhydrides from Carboxylic acids Anhydride = “without water” 20.9 Conversion of Carboxylic Acids into Acid Chlorides and Anhydrides

Problem The second reaction on the previous page happens through a nucleophilic acyl substitution reaction. Draw the mechanism. What product might you get upon heating of succinic acid?

Reduction of Carboxylic Acids The powerful reducing agent LiAlH4 is required NaBH4 does not reduce carboxylic acids The overall sequence for reduction is summarized as: 20.10 Reduction of Carboxylic Acids to Primary Alcohols

Problems Draw the reactant that forms the following product upon reduction with lithium aluminum hydride: How might you prepare 2-phenylehtanol from benzyl bromide? More than one step is necessary.

Decarboxylation of Carboxylic Acids Decarboxylation: The loss of CO2 from RCO2H Most ordinary carboxylic acids do not participate, but the following types do: 1. b-keto acids 2. Malonic acid derivatives (diacids) 3. Carbonic acid derivatives 20.11 Decarboxylation of Carboxylic Acids

Decarboxylation from b-keto acids 20.11 Decarboxylation of Carboxylic Acids

Decarboxylation from Malonic Acid Derivatives This reaction also does not occur in base

Decarboxylation of Carboxylic Acids Decarboxylation from carbonic acid derivatives

Problems Give the products for the following reactions:

Draw the mechanism for the decarboxylation reaction below: