[greentea11]

Going from diethyl malonate:
https://www.google.co.uk/search?q=work+up+after+alkylation&source=lnms&tbm=isch&sa=X&ei=o9f7Usf2EZGM7AbC9YHgBA&ved=0CAcQ_AUoAQ&biw=1366&bih=600#q=diethyl+malonate&tbm=isch&facrc=_&imgdii=_&imgrc=a4nxHmSq6poVpM%253A%3BP03ta_KO_HPd2M%3Bhttp%253A%252F%252Fwww.pherobase.com%252Fpherobase%252Fgif%252Fdiethyl%252520malonate.GIF%3Bhttp%253A%252F%252Fwww.pherobase.com%252Fdatabase%252Fkovats%252Fkovats-detail-diethyl%252520malonate.php%3B450%3B207

to glutaric acid
https://www.google.co.uk/search?q=work+up+after+alkylation&source=lnms&tbm=isch&sa=X&ei=o9f7Usf2EZGM7AbC9YHgBA&ved=0CAcQ_AUoAQ&biw=1366&bih=600#q=glutaric+acid&tbm=isch&facrc=_&imgdii=_&imgrc=9nMMLcLgUOppVM%253A%3B9uszslW8qvY7EM%3Bhttp%253A%252F%252F0.tqn.com%252Fd%252Fchemistry%252F1%252F0%252FO%252FH%252F1%252FGlutaric_acid.jpg%3Bhttp%253A%252F%252Fchemistry.about.com%252Fod%252Ffactsstructures%252Fig%252FChemical-Structures---G%252FGlutaric-Acid.htm%3B400%3B123


I'm struggling to come up with a mechanism for this synthesis

I thought of hydrolysing both ends of the ester to give a dicarboxylic acid, then you could decarboxylate it, but I don't know how to create the longer carbon chain in the product? any hints?

Is there a straightforward mechanism I've overlooked here?
any help much appreciated

[Dan]

What kind of reactivity does diethyl malonate exhibit?

How can you append new chains to it?

Hint: Decarboxylation will be the final step.

[zsinger]

Further Hint:  Does Diethyl Malonate have any "special resonance" that allows it to be alkylated "somewhat" easily?  Have fun!
             -Z

[greentea11]

thanks for the hints!

 so did ester hydrolysis to form dicaboxylic acid, then used the enol form to add another chain with a carboxylic acid to extend the chain for the product, then decarboxylated the original second carboxylic acid group

sound good?

[orgopete]

This sequence is covered in probably every organic chemistry textbooks. I suggest you follow the suggested path rather than proposed alternate.