Differences between alkyl halides and alkyl tosylates What are the functional differences between alkyl halides alkyl tosylates? Both halides and tosylates are good leaving groups, yes. But is there chemistry that one will do and the other won't? Etc.? I'm not worried about their relative leaving group abilities. My prof treats the two as equivalent but I can't help but wonder if this is an oversimplification. Wikipedia doesn't point out any differences. The only difference I can think of is that an alkyl tosylate is an ester ... and this opens up the world of ester chemistry - i.e. hydrolysis with hot concentrated acid. Where as I can't see alkyl halides reacting in hot concentrated acid.
Both can be leaving groups. In general, TsO- are better leaving groups, thats why they are often specifically used as so. Halides can be used in many more reactions, like preparation of organometallic compunds.
TsO- more common function is to transform an alcohol group in a good leaving group. Formation of an halide, usually is not the way to go in this case.

But their basic reactivity is very similar.
If you dive into more complex reactivity, you can complicate things to a very very large extent...