Then the orthoester is converted in high yields to {HEAD ~ the corresponding imidic ester} by {TAIL ~ condensation} with an aniline while simultaneously removing alkanol from the reaction mixture to drive the equilibrium reaction to completion 
by
Then the orthoester is converted in high yields to { HEAD ~ the corresponding imidic ester } by { TAIL ~ condensation } with an aniline while simultaneously removing alkanol from the reaction mixture to drive the equilibrium reaction to completion
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH