Preparation and reactivity of a macroporous polymer-supported organotin hydride catalyst

Organometallic Polymers of Germanium, Tin and Lead

“…The high permanent porosity of the supports obtained enable the polymer-supported organotin chlorides 79 to reduce 1-bromoadamantane using NaBH 4 as hydride source. The reactivity of 79 is comparable with that of tributyltin chloride 174 . The polymer-supported organotin chloride 79 exhibits a relative high intrinsic stability, as was shown by several uses without loss of activity and without need of regeneration.…”

“…Various insoluble polymers 88b were prepared by the radical copolymerization of dibutyl [3-(allyloxy)propyl]tin chloride, PMI, as a chain diluent, and MPBMI as cross-linking agent. These polymers exhibited higher swelling capacities in toluene than those of macroporous organotinfunctionalised polystyrene resins 174 . The rather low specific surface areas as determined by BET analyses were in the range of 3-23 m 2 g −1 indicating the polymer structure to be more gel-type than expected, which in turn is the result of the poor cross-linking ability of the bismaleimide under the polymerization conditions employed.…”

Influence of the support structure on the activity, stability, and metal leaching of a polymer-supported organotin chloride catalyst

“…9 The results obtained are reported in Figure 1. The conversion of bromoadamantane to adamantane reached 80% after 1 h and is complete within 6 h. These results are comparables with those obtained with supported species P1.…”

“…Having this in mind, some time ago we started a project concerning the synthesis and copolymerization of monomers bearing organotin functionalities to obtain macroporous beads with adjustable crosslinking levels and tin loading. 9,10 It was expected that better site-isolation obtained with these more rigid network would limit the deactivation of the reactive tin moiety and increase the turnover and life-time of the supported catalysts thus obtained. In a previous article, 9 we developed a polymer-supported organotin catalyst P1 based on dibutyl([2-(4-vinylphenyl)ethyl)] tin chloride 1.…”

“…9,10 It was expected that better site-isolation obtained with these more rigid network would limit the deactivation of the reactive tin moiety and increase the turnover and life-time of the supported catalysts thus obtained. In a previous article, 9 we developed a polymer-supported organotin catalyst P1 based on dibutyl([2-(4-vinylphenyl)ethyl)] tin chloride 1. This macroporous support was synthesized using 1 as the functional monomer, and (E) 1,4-bis (4-vinylphenoxy) but-2-ene (BVPB) as the crosslinking agent showed a good activity and recycling ability when used as a catalyst in the reduction of bromoadamantane to adamantane by NaBH 4 .…”