| Popis: |
Polystyrene-supported 1,8-diazabicyclo[5.4.0]undec-7-ene (PDBU) was prepared by the reaction of lithiated 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) with chloromethylated or ω-bromoalkylated polystyrene resins. PDBU is effective as reagent for dehydrobromination and esterification. The reactivity of PDBU in dehydrobromination is lower than that of DBU. In the case of esterification, PDBU with 19% ring substitution exhibits almost the same reactivity as DBU. PDBU, regenerated from the hydrobromide salt, can be re-used without decrease in reactivity. |
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