Preparation, Characterization, and Application of Polymer-Supported Stannols and Distannoxanes

Abstract

Novel organotin copolymers derived from poly-3- and poly-4-(2-di-n-butylchlorostannyl)ethylstyrene-co-divinylbenzene-co-styrene have been prepared. The copolymers were prepared with various proportions of monomers and converted to organotin oxides and organotin carboxylates. Copolymer-bound organotin oxides, as a mixture of stannol and distannoxane, have been shown to catalyze the lactonization of hydroxycarboxylic acids.

Stannylated Polynorbornenes as New Reagents for a Clean Stille Reaction

“…The use of a tin-containing polymeric matrix has met with success in other organic reactions such as free radical processes, [10] transesterification reactions, [11] allylation of aldehydes, [12] halogenation of aromatic amines, [13] lactonization, [14] and other reactions, [15] but only a few attempts have been made to use polymeric tin reagents in the Stille reaction [16] or in the catalytic tin Stille vinylation mentioned above [17] The polymers used in all these reactions are polystyrene resins, most of them synthesized by functionalization of preformed polymer supports. In the case of the Stille reAbstract: New functionalized polynorbornenes have been obtained in good yields by vinylic copolymerization of norbornene with a (norbornenyl)SnBu 2 Cl monomer, catalyzed by [Ni-…”

Cross-linked resins functionalized with triorganotin carboxylates: synthesis, characterization and preliminary catalytic screening in transesterification

“…In this context, several cross-linked polymers bearing organotin moieties in the side chain have been synthesized, generating socalled clean organotin reagents; their syntheses are often complex and multi-stepped, but their final performances as a heterogeneous transesterification catalyst are usually satisfactory. 7,8 In connection with our interest in triorganotin carboxylates as anion carriers, 9,10 we recently observed that these materials can also be used as transesterification catalysts, likely due to the Lewis acidity of the tin atom, which is affected by the presence of the carboxylic moiety. This finding looks very attractive, since it offers the possibility of easily grafting…”

Organometallic Polymers of Germanium, Tin and Lead

“…Two stannol moieties, which are close to one another, can form distannoxanes by a condensation reaction, whereas isolated stannols remain unchanged. The reaction of the polymer-supported din-butyltin chloride 79 with sodium 4-methylbenzoate was also reported (Scheme 37) 170 The homopolymerization of 83 gave a soluble polymer of relatively low molecular mass (M n = 8.4 × 10 3 ), but the average molecular weight increased with increasing content of styrene co-units in the copolymer. For a TBTSP-to-styrene ratio of one-to-four, a polymer with M n = 1.5 × 10 4 was obtained.…”

“…The polymer 79 was reacted with sodium hydroxide in EtOH/H 2 O to give a mixture of stannol 80 and distannoxane moieties 81 in ratios depending on the tin-loading capacities of the starting polymers 170 . The ratio was not changed upon heating at reflux the polymer in a benzene/water mixture.…”