Help with finding chirality centres

[andrewvidler]

I am having a lot of trouble with this. Does anyone know how to identify the chiral centres in the following attached molecule?

 

[Borek]

What methods of recognizing chiral carbons do you know?

Please note that attaching .doc files is not a good idea - many people are reluctant to open them, as they can contain viruses. In such a case best approach is to attach an image.

Edit: I think I am bored, I have replaced doc with png in your post.

 

[andrewvidler]

Hi Borek - i know the basics, ie a carbon with 4 different substituents is a chiral carbon, however i have been given complex molecules that have multiple chirality centres and i cannot see them. For instance the attached image has 4 - but i can't see why.

 

[Borek]

Perhaps you are thrown off by cycles?

Select an atom, move out from it in each direction and compare atoms on the way. If you get to the same place from both sides and there were no differences on the way - atom is not chiral.

Try it on some simple molecules first, say cyclohexanol and 2-methylcyclohexanol.

 

[andrewvidler]

Hi - how about this one? I am confused as to what constitutes a different group. I mean how far do go along the separate branches from the ceontre to say that is a differernt substituent.
this is one where it days there are 3. I know where they are but i don't see why

 

[Borek]

how far do go along the separate branches from the centre to say that is a differernt substituent

Either till you "meet" or till you find a difference - whichever comes first.