The transformation of cocaine in crack cocain is made by a process consisting of mixing water, cocaine and baking soda. From what i've understood, the basicity of baking soda allow it to deprotonize the amine of the cocaine, transforming it in it's basic form.
I've heard many times from drug users that the process also purify the cocaine of it's adulterants.
Would the freebasing process also transform some alduterants to freebase in the process ? After checking the adulterants, i wonder if some adulterants might also transform in their basic form during the process, especialy some adulterants being structurally close to cocaine and also having an amine like :
Lidocaïne :
Procaïne :
Or Phenacetine :
or Paracetamol :
I apologize for the unequal size of the image, i've found them all online