[doof]

forgive my ignorance, i'm a biologist not a chemist, but what is the best way to replace a carboxylic acid group on a chemical with an amine group? can this be done in 1 reaction or do i need to remove the hydroxyl group group first, then the acyl group and then add the amine group all in separate reactions? having added an amine group is it then possible to add another carbon to the amine group?

Additionally what is the best way to substitute an amine group with a CH3 group?

I really hope these questions make sense to someone lol

thanks

[doof]

Oh and one more thing, if anyone knows of any enzymes that can perform these functions that would be good to know too

[Dan]

The Schmidt reaction immediately springs to mind, but it's quite harsh and HN₃ is very toxic - what other functional groups are present?

[sjb]

By

... having added an amine group is it then possible to add another carbon to the amine group?

Additionally what is the best way to substitute an amine group with a CH3 group?

Do you mean e.g. RNH₂ to RNHMe, or RNH₂ to R-Me ? The former is probably easier, look into http://en.wikipedia.org/w/index.php?title=S-Adenosyl_methionine&oldid=332061647 or similar. Whilst the latter is probably possible, perhaps via imines, cleavage, reduction etc, it may be easier to start from your acid, if that's what you're after.

[stewie griffin]

The Curtius Rearrangement (http://www.organic-chemistry.org/namedreactions/curtius-rearrangement.shtm) will get the job done for going from carboxylic acid to amine in one step. Note that you don't have to go through the acid chloride like the link above mentions. Instead just start with the carboxylic acid and some diphenylphosphoryl azide to do it in one step (http://en.wikipedia.org/wiki/Curtius_rearrangement). The Curtius reaction is similar to the Schmidt reaction that Dan mentioned, but you don't have to use the toxic HN₃.

[doof]

Cool, thanks guys, i think that helps me

[Grundalizer]

forgive my ignorance, i'm a biologist not a chemist

muahaha they should make all the bio majors at my school wear those while in the science building

[g-bones]

If you do not wish to go through the acid chloride, you can go straight through the curtius rearrangement with the carboxylic acid if you treat it with DDPA in something like Et3N and work it up with a solution of lithium hydroxide.  this will get the job done in one reaction.