Development of Heterogeneous Thiol-Ene Polymer Beads and their Applications in Polymer-Supported Organocatalysis

Abstract

Siden tusenårsskiftet har reaksjoner katalysert av ikke-metallholdige organiske molekyler (organokatalyse) økt i popularitet. Organokatalysatorer opererer under milde reaksjons betingelser og via flere aktiviseringsmoder. Organokatalyse har etter hvert opparbeidet seg et solid rykte innen asymmetrisk syntese. Samtidig har det var vanlig å forankre organokatalysatorer på polymere partikler. Disse muliggjør enkel separasjon av organokatalysatoren fra reaksjonsmediet samtidig som polymerene kan gjenbrukes. Det er dermed interessant å utvikle nye metoder for å syntetisere disse polymer-bundne organokatalysatorene. Arbeidet som fremgår i denne avhandlinger tar sikte på å utvikle en ny metode for å forankre organokatalysatorer til polymere partikler via en polymeriseringsteknikk som bruker koblingen mellom tioler og alkener.

Since the year 2000 chemical transformations promoted by non-metallic organic catalysts (organocatalysts) have experienced an explosive interest. Operating via benign conditions and via many modes of activation, organocatalysis is considered to be a mature field within catalysis. The preparation of heterogeneous polymer-supported organocatalysts is of special interest since they allow easy separation of the catalyst from the reaction medium. The polymer-supported catalysts can also be recycled often keeping the same catalytic efficiency for many cycles. Inventing new methods to prepare polymer-supports and by extension polymer-supported organocatalysts are thus of interest in organocatalysis. The work presented in this thesis aim to prepare these heterogeneous polymer-supported organocatalysts by taking advantage of a free radical thiol-ene coupling reaction polymerisation developed in our group. Several polymer-supported organocatalysts were synthesised via this method.