I don't think i've ever taught an A-level chemistry student that hasn't said this at some point. Because it is the part of chemsitry (in my opinion) that seems the most daunting. I generally wait until towards the end of the year then go through drawing an organic sythesis tree with them. Depending on the way that they learn best, which hopefully by then I will have worked out, I propose a few tips for rote learning.
Compounded with the understanding of the fundamentals of chemistry we would have built up in previus sessions, by that point it seems a lot less daunting. Thank you for reading.