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The binding of Lewis bases to organoboron polymeric Lewis acids has been studied and the parameters that determine the complexation equilibrium have been investigated, which include (i) the strength of the individual Lewis acids and Lewis bases, (ii) concentration, and (iii) temperature. While the strongly Lewis acidic borane polymers poly(4-bis(pentafluorophenyl)borylstyrene) (PS-BPf) and poly(4-(di-2-thienylboryl)styrene) (PS-BTh) form isolable complexes with strong Lewis bases such as 4-t-butylpyridine (tPy), a temperature dependent equilibrium is established with weaker bases such as THF. Similarly, the weakly Lewis acidic boronate polymer poly(4-diethoxyborylstyrene) (PS-BOEt) undergoes a temperature dependent equilibrium with the strong Lewis base 4-dimethylaminopyridine (DMAP), while poly(4-pinacolatoborylstyrene) (PS-BPin) does not significantly bind to pyridine bases. Decomplexation of PS-BTh· t Py is achieved by treatment with the stronger Lewis acid, B(C6F5)3, thereby confirming the reversible nature of the polymeric Lewis acid–base adducts.

Different preparative routes for the attachment of organoboron moieties to polyolefins and applications of such materials are reviewed. Preparation from boron-functionalized monomers represents one possible synthetic strategy with free radical polymerization, Ziegler–Natta polymerization, and ring-opening metathesis polymerization methods as the most thoroughly studied procedures. Recent advances in the preparation of boron-containing polymers through polymer modification reactions provide an interesting alternative that allows for the facile preparation of well-defined organoboron polymers of various architectures including homo polymers, random copolymers, block copolymers, and telechelic polymers. New opportunities for organoboron polymers as supported catalysts, sensors, luminescent materials, device components, and precursors to ceramics are briefly discussed.

A series of poly(ferrocenylsilane)s containing chloroalkyl side chains of increasing length is reported. By reacting fcLi2· $$\tfrac{2}{3}$$ tmeda with Cl2SiMeR, the corresponding [1]ferrocenophanes were prepared (2a, R=CH2Cl; 2b, R=CH2CH2Cl; and 2c, R=CH2CH2CH2Cl). Transition metal-catalyzed or thermal ring-opening polymerization (ROP) of these monomers yielded the polyferrocenes 3a, 3b, and 3c. The chlorine substituents of polymers 3a and 3b were unreactive toward nucleophilic substitution. In contast, polymer 3c could be reacted with 4-dimethylaminopyridine in DMF to afford the water-soluble poly(ferrocenylsilane) 4. This represents a new method for the preparation of water-soluble polyferrocenes.