Chlorogenic acid has nothing to do with chlorine. Basically
greek work "chloros" means green. The nomenclature of this compound
is derived because of its solution color.
Chlorogenic acid is derived from GREEN coffee beans, alkaline
solutions turn GREEN upon exposure to air. lamely put "green
color"- "genic" producing.
Chlorine is also derived from the same greek work. Chlorine is a
green gas and hence related to chloros. Similarly chlorophyll and
chlorite.