[icho2013]

Can you help me this problems
There are three possible products from this compound with sodium borohydride . What are their structures?
Thanks you.

[UG]

Do you have any ideas on what might happen? Do you know the properties of sodium borohydride and the reactions with aldehydes and ketones? You will need to find out if you are going to make it to IChO 2013 

[Dan]

Show your attempt: Forum Rules.

Did you look up sodium borohydride in the index of your textbook? What does it do?

Also, attach images to your post instead of .pdf, more people will see it. For the benefit of others, the structure is attached below.

[icho2013]

In my opinion , i think 2 products are 2 ancol , and the last one is hecmiaxetal ( i think it not true)

[orgopete]

Hint: I think this problem is asking a question about stoichiometry. Let us assume that for one mole of ketoaldehyde there is 1/4 mole of borohydride (since NaBH4 can deliver four hydride atoms). If that is the case, then some ketoaldehyde is recovered, but it is not counted among the products as it is a starting material. What are the products?

[qw098]

Have you guys seen intramolecular reactions and/or nucleophile/electrophile chemistry in your class yet? Think about what sodium borohydride can do and what the corresponding functional group change can do as a reaction on the rest of the molecule

[orgopete]

Have you guys seen intramolecular reactions …

I am not aware of NaBH4 catalyzing an intramolecular reaction with this substrate. What are you proposing?

[qw098]

Have you guys seen intramolecular reactions …

I am not aware of NaBH4 catalyzing an intramolecular reaction with this substrate. What are you proposing?

I am proposing that the NaBH4 reduce one of the carbonyls to an alcohol and then the alcohol act as a nucleophile to attack the electrophilic carbonyl on the other side.

[icho2013]

I'm really sorry, but this problem is not enough difficult that we think.
3 products are 3 ancol , thanks you very much.

[orgopete]

Those are the products I was thinking of.

[qw098]

Those are the products I was thinking of.

Me too. But there could be an intramolecular reaction between the newly formed hydroxyl and the carbonyl carbon.

[orgopete]

…But there could be an intramolecular reaction between the newly formed hydroxyl and the carbonyl carbon.

If you do, I suggest you make a model of it.

[qw098]

…But there could be an intramolecular reaction between the newly formed hydroxyl and the carbonyl carbon.

If you do, I suggest you make a model of it.

I could draw a bridge across the benzene ring, no? from carbon 1 to carbon 4

[CaverKat]

Mmmm, bicyclic aldol?  Dunno, benzene's pretty flat, and with the extra conjugation of the ketone... but shouldn't happen with NaBH₄, right?

I love over-thinking things!

[Dan]

I could draw a bridge across the benzene ring, no? from carbon 1 to carbon 4

As suggested, make a model. While you can draw it, you won't be able to model it (too strained).