How do I prepare the following compound from diphenylmethane? I am having trouble with the preparation of this product from diphenylmethane as a starting material. One of my thoughts was to attach the butene into the structure, but I don't see how it is viable. So I would like some suggestions on how to proceed, and also with the name of the compound (butenediphenylmethane?).
Here's a mechanism that I thought of (It's more theoretical than practical):



Bromination in the first step will occur at the benzyl position due to a stable free radical. Sodium Propynide then adds more carbon atoms via the SN2 mechanism, which are then reduced with Lindlar's catalyst to give the cis-alkene.

The name of this compound should be (Z)-1,1-diphenylbut-2-ene, but as pointed out in the comments, the preferred IUPAC name (PIN) seems to be (Z)-but-2-ene-1,1-diyldibenzene (verified by ChemDraw)