9,10-dihydro-9,10-ethanoanthracene derivatives. Stereoisomers or different compounds? What are their chemical names?

What is the relationship between these compounds? Are they stereoisomers or some of them are different compounds? Additionally, what would be their names?


(For position 9, with the methyl substituent)
Green and Cyan -> S configuration
Orange and Purple -> R configuration


Trying to name them by having the antracene ring system as a core all of them would have a name starting as "2-Chloro-" and then R or S, but in this way, the green-cyan and purple-orange compounds would have the same name. Is there another way to name these?


[![enter image description here](https://i.stack.imgur.com/gZXwU.png)](https://i.stack.imgur.com/gZXwU.png)




Green and orange are enantiomers, as are purple and cyan.


The remaining relationships are all diastereomeric. I think your problem is that you arent considering the carbons at the bridgehead positions as stereocentres too (which they are).


 0