text: One of the simplest reactions entails condensation of formaldehyde and dimethylamine.  This reaction produces first the carbinolamine (a hemiaminal) and bis(dimethylamino)methane ():
  The reaction of  formaldehyde with  carbazole, which is weakly basic, proceed similarly:
  Again, this carbinol converts readily to the methylene-linked bis(carbazole).