Polymer-supported synthesis as a tool for improving chemoselectivity: Pauson-Khand reaction
摘要:
Intermolecular Pauson-Khand (PK) reactions of norbornene-derived substrates have been carried out with several alpha,omega-alkynols under both normal homogeneous conditions and with the alkynol bound to functionalized Merrifield's polymer beads. With 2% crosslinked resin chemoselectivity Favoring PK product Formation over alkyne trimerization and other related side reactions is enhanced over that found either in solution or on 1% crosslinked polymer. Alkynol chain length and nature of the linker also significantly affect the outcome of the polymer-supported process. (C) 1997 Elsevier Science Ltd.