Polymer-bound allyl sulfones (cf. 9) were utilized in geminal cycloalkylations with epichlorohydrin to generate a cis-phenylsulfonylcyclobutanol derivative (cf. 11) in one step. In the final step of this solid-phase synthetic sequence, cuprate, organomolybdenum, and organopalladium reagents were screened to obtain an optimal protocol for “traceless” cleavage of cyclobutylidene products from the resin. Among these, palladium-catalyzed allylic alkylation was the most efficient. In addition, highly regioselective nucleophilic attack at the less hindered terminus of the allyl fragment (i.e., overall SN2‘ sulfinate displacement) was observed. Cyclobutylidene diversification was demonstrated by incorporating different allylic substituents, O-functionalizations, and C-nucleophiles to prepare a demonstration library of eight cyclobutylidene derivatives (i.e., derivatives of 4) in four steps and 30−38% overall yield from lithium polystyrene/divinylbenzene sulfinate.

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Similar enantiomeric excesses as for analogous monomeric sulfonamides are provided by the chiral resin 1 (connections to the polymer are shown as circles) when it is used as catalyst for the reductive alkylation of aromatic aldehydes and for the cyclopropanation of cinnamyl alcohol.

Ähnliche Enantiomerenüberschüsse wie analoge monomere Sulfonamide liefert das chirale Polymer 1 (Polymeranbindung als gerasterte Kreise gezeigt), wenn es als Auxiliar bei der reduktiven Alkylierung von aromatischen Aldehyden und der Cyclopropanierung von Zimtalkohol eingesetzt wird.