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

摘要

Very efficient syntheses of `long' bisphenol and activated dihalide monomers containing keto groups were developed on the basis of α-aminonitrile chemistry. Known and novel activated dihalide monomers were obtained in quantitative yields and without isomeric impurities. This method is suitable for any activated dihalide by reaction with 2 equiv of the anion of p-fluorobenzalaminonitrile (8), followed by hydrolysis to produce a monomer with two more p-fluorobenzoyl units. Similarly, use of the anion of p-methoxybenzalaminonitrile (15) by reaction with activated dihalides provides a general route to bisphenols. Less expensive dichloro monomers, e.g., 4,4 prime -dichlorobenzophenone, can be used to synthesize these `long' bisphenol and activated dihalide monomers.