Chirality of Naproxen: Explaining With CIP Rules

[miniradman]

Homework Statement

determine and explain its chirality using the CIP rule
*see attached image*

Homework Equations

CIP rules

The Attempt at a Solution

Hello

I've determined that the stereocenter of this molecule is at the carbon where the carboxyl group meets the two benzene rings.

I've done step one and rotated the stereocenter such that the hydrogen is facing back. However when deciding the priorities of the three constituents on the stereocenter I get a little confused.

When going down the chain, towards the aromatic rings that I'll encounter a double bond. I tried reading how these fit in with the CIP rules but I find them to be quite ambiguous.

And with the carboxyl group, when going down the chain, which direction do I have to go? Down the hydroxyl group on the double bonded oxygen? I

Thanks
- miniradman

 

[ChiralWaltz]

You have identified the correct chiral center. These are the three groups I see.

Methyl
Ring
Carboxylic acid

I do not know what CIP rules are.

 

[Borek]

Cahn–Ingold–Prelog

 

[Yanick]

Your chiral carbon is attached to:

1) A hydrogen.
2) A carbon which is attached to 3 or so oxygen atoms (because m.ultiple bonds are counted as equivalent number of single bonds, from memory)
3) a carbon which is attached to 3 carbon atoms (same as above).

Can you do it now?

 

[miniradman]

Your chiral carbon is attached to:

1) A hydrogen.
2) A carbon which is attached to 3 or so oxygen atoms (because m.ultiple bonds are counted as equivalent number of single bonds, from memory)
3) a carbon which is attached to 3 carbon atoms (same as above).

Can you do it now?

Well since oxygen has a higher atomic number than carbon, I assume the carboxyl group has more priority.

However, intuitively, if I were to have another single aromatic ring in place of the carboxyl group, how would I go about going down the branches? Which would then be of highest priority? I get confused on where to go once you start having to decide which branch to take.