An oxidizing agent, preferably sodium dichromate, is added to {HEAD ~ the solution} to couple {TAIL ~ the diamine} and aniline derivative 
An oxidizing agent , preferably sodium dichromate , is added to { HEAD ~ the solution } to couple { TAIL ~ the diamine } and aniline derivative
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH