HCTU

HCTU is an excellent coupling reagent that suppresses racemization. It is more reactive than
HBTU, but not reactive as HATU. However HCTU is lower in cost than HATU. HCTU may
produce higher coupling yield in difficult coupling reactions than HBTU. Couplings using HCTU
proceed smoothly and can be enhanced by adding 6-Cl-HOBt.