To answer your question: yes, we already create synthetic caffeine. It's widely used in soda, energy drinks, etc.
Does this mean the end of soda as well?
http://www.npr.org/sections/thesalt/2014/03/13/289750754/wak...
There's a niche in the market for somethig that tastes nice, is cold, isn't full of sugar and is not caffeinated.
Ice water?
(and I'm saying this as a cola enthusiast)
(my point being more that marketers probably won't call what you are looking for cola, not the pedantry)
> "But most of the caffeine used in soft drinks is actually synthetically produced in Chinese pharmaceutical plants."
http://www.npr.org/sections/thesalt/2014/03/13/289750754/wak...