2
$\begingroup$

enter image description here

I took a much different approach from the solutions manual. My synthesis:

1) H2 and Lindlar's catalyst to stop at the alkene.

2) Oxidative cleavage to form benzoic acid. Works here because we have a benzylic hydrogen.

3) Addition of excess allyl alcohol with catalytic concentration of acid and heat. A Fischer esterification step.

This is also one fewer step than what my solution's manual has. The solutions manual went up to the acid chloride and down to the ester, which is a nice step (avoids the heat). Does mine also work on paper?

$\endgroup$

2 Answers 2

5
$\begingroup$

No, your approach doesn't give the right product. There's a carbon missing between the benzene ring and the carbonyl carbon. See the difference in the products below.

I don't know exactly what your solutions manual suggested, but I've included a conservative approach through phenylacetaldehyde. As you suggest, it's not absolutely necessary to go through an acid chloride to make an ester from a carboxylic acid. The Fischer esterification will work. Also, for many carboxylic acid to ester conversions, you can simply react the carboxylic acid with thionyl chloride and the desired alcohol all in the reaction together, rendering it a one-step transformation.

enter image description here

$\endgroup$
0
$\begingroup$
  1. bake starting material in Wilgerodt-Kindler reaction (it works on phenylacetylene too)
  2. hydrolyze to phenylacetic acid
  3. esterify
$\endgroup$
1
  • $\begingroup$ Could you possibly add some more detail here? At the moment this is just a statement with no real explanation of the reasons behind it and as such it will probably be deleted. $\endgroup$
    – bon
    Commented May 14, 2015 at 18:56

Not the answer you're looking for? Browse other questions tagged or ask your own question.