Melatonin->5-MeO-MET

[Rhodium]

I believe that the isobutanol was chosen because of its boiling point (106°C). If you cannot aquire that, you could either use isopropanol (and hope that 82°C is enough if you use a longer reaction time, say 4h), or you could use a mixture of 75% ethylene glycol (bp 192°C) with 25% toluene (bp 110°C) added to limit the reflux temperature.

Odd that you found dithionite with carbonate added - are you sure you cannot find the pure stuff anywhere?

[yellium]

It's not only N2. A reaction which only works under N2 usually also means `requires rigorously dried solvents, dry N2, no traces of water whatsoever, or else you're fucked'. You just can't solve that by flushing a bit with He. Unless you are trying to do LAH reductions in a US state with over 100% humidity. 
When all you've got is a nailgun, every problem looks like a messiah...