Today I was considering to answer the question "Which tautomer of hexane-2,4-dione is more stable?" I wanted to run a few calculations and while preparing a directory structure I wanted to make sure that I used correct and unique names for the compounds. I am citing the picture in the named question:
I was going to derive the names of the structures from the parent compound hexane-2,4-dione. Hence I would have named compound 1 (Z)-2-hydroxyhex-2-en-4-one and 2 (Z)-4-hydroxyhex-3en-2-one.
When I recreated the above picture in ChemBioDraw and used it to autogenerate the name, the result for 1 was different: (Z)-5-hydroxyhex-4-en-3-one. See below.
I am no expert on nomenclature and I do not have the blue book handy. Usually I rely on the names generated through software. Most of the times they are accurate enough to name a compound unambiguously and that is often what I am going for.
I understood from this answer, P-14.3.5 Lowest set of locants, that I should use the 4,2,2 set over the 5,3,2.
Is my thinking correct and the auto-generated names are wrong, or is the software correct and my thinking is wrong?