Sreedhar,

We can try with benzotriazole. First treat carboxylic acid (ArCOOH) with thionyl chloride followed by benzotriazole(BtH) in THF, it gives ArCOBt. Then react ArCOBt with desired amine.This is a selective coupling procedure. We can do the above entire sequences as one pot. I hope it will help you

DCC,HOBT and base.try this one in DCM media or EDC media.these are useful for amide bond formation even OH present.

aryne reaction...................

Sreedhar,

We can try with benzotriazole. First treat carboxylic acid (ArCOOH) with thionyl chloride followed by benzotriazole(BtH) in THF, it gives ArCOBt. Then react ArCOBt with desired amine.This is a selective coupling procedure. We can do the above entire sequences as one pot. I hope it will help you

HATU, or convert the acid into acetyl chloride first.

I used PyCIU coupling reagent.dissolve this coupling reagent in DCM with carboxylic acid and add base like DIPEA and stirring for 15 min to generate acid chloride,finally add amine and stirring for 30 min, but this with aliphatic amine. if you want to work with aromatic amine, the reaction time should be more than 3 hours.

See synthesis of drugs in www.drugsyn.org

Try with DCC or DEAD in presence of triphenyl phosphine

Edc, hobt, nmm, dmf

carboxylic acid, DCC, NHS in Dry DMF media or EDC. These are useful for amide bond formation even in the presence of OH.