If we can say "I am running to catch the train", is it also appropriate to say that "I am going to the office early to catch the boss"?
I talk about "catching so-and-so before he leaves for the day" and similar wording all the time, and I've heard many others use it routinely. I'm frankly surprised by those who say they'd only use it when the boss is not around or that it would depend on their relationship to the boss. I'd never thought of it as offensive or demeaning or anything like that.
Note that "catching someone" is also used to describe having a romantic relationship, especially from the woman's point of view. As in, "Sally wants to catch Bob". And there's an idiom that "So-and-so is a good catch", meaning he is a man that women would consider a desirable husband because of his wealth, status, manners, good looks, etc.
Catching a train is idiomatic (you're not running to grab hold of it physically while it is moving - see 6th definition of catch at Dictionary.com). Catching the boss is sometimes used, especially with a before prepositional phrase (I've got to catch the boss before he leaves today), but that meaning of catch is only informal.
More formal would be I am going to the office early to see the boss.