A polyketone synthesis involving nucleophilic substitution via carbanions derived from bis(alpha-aminonitrile)s. 5. A new, well-controlled route to "long" bisphenol and activated aromatic dihalide monomers

Very efficient syntheses of "long" bisphenol and activated dihalide monomer s containing keto groups were developed on the basis of alpha-aminonitrile chemistry. Known and novel activated dihalide monomers were obtained in qua ntitative yields and without isomeric impurities. This method is suitable f or any activated dihalide by reaction with 2 equiv of the anion of p-fluoro benzalaminonitrile (8), followed by hydrolysis to produce a monomer with tw o more p-fluorobenzoyl units. Similarly, use of the anion of p-methoxybenza laminonitrile (15) by reaction with activated dihalides provides a general route to bisphenols. Less expensive dichloro monomers, e.g., 4,4'-dichlorob enzophenone, can be used to synthesize these "long" bisphenol and activated dihalide monomers.