Is h-index important? Can h-index be used to classify yourself to know whether you are at a given academic rank?
As with all bibliometrics, the h-index is indicative at best. There is no magic number that says "now give this person a promotion", but if you have an h-index twice that of your colleagues, it might suggest something interesting.

If you really want to use the h-index to see how you compare to other organic chemists, why not look at the h-index of your colleagues, collaborators, or of researchers at the department you're applying to? You will already have a sense of their relative position, you'll be familiar with their work, and it'll help you get a sense of what the h-index might mean in your specific field - as well as the amount it varies between individuals you'd think of as comparable.

(Make sure to calculate all h-indexes using the same citation data, though. You'll get confusing results if some use Web of Science data and some Google Scholar...)