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Can pseudochirality be considered when three or four groups on the carbon atom are constitutionally the same, but configurationally different?
For example, when the C atom is bonded to one H, and then three more structurally identical groups with 2 chiral C each - in configurations R,R and S,S and R,S respectively - then by assigning each of the 4 groups a priority value (since they are all different - though 3 have the same structure) we can assign a configuration to this C atom.
Ah, now I think I understand what you're asking. You're saying that we have a central carbon to which is attached a hydrogen and 3 groups with the same structure. Each of these 3 groups contains 2 chiral carbons. One group is R,R one is R,S and one is S,S.
So yes, the chirality of the central carbon (it is chiral, it is not meso or prochiral - there is no plane of symmetry bisecting the central carbon) can be assigned using the Cahn–Ingold–Prelog priority rules where "R" has higher priority than "S". Therefore the priority ranking around the central carbon in your molecule would be R,R > R,S > S,S > H.
