How do I assign priorities to substituents with triple bonds?
If we take a look at the molecule above, the atom directly bonded to the asymmetric center is carbon for all three substituent.
Moving on to the atoms connected to those carbons, benzene side has carbons attached by a double bond and a single bond. The double bond is counted twice and the atoms count as \ce{C, C, C}.
For the sp carbon on the lower right, it is triple bonded to its neighboring sp carbon, so it counts as \ce{C, C, C} as well.
The tert-butyl group is bonded to three carbons from methyl groups, so this gives another \ce{C, C, C} making it a tie again.
If we look at the next set of atoms, the tert-butyl group has methyl groups so it's \ce{H, H, H}, giving it the lowest priority.
However, I'm not sure how to count the next set of atoms for benzene and the triple bond containing group. Judging from the R, S configuration the benzene group should have a higher priority, but I'm not sure how to figure that out. What should be my next step?
