Total synthesis of aigialomycin D: surprising chemoselectivity dependence on alkyne structure in nickel-catalyzed
Christa C Chrovian1, Beth Knapp-Reed, John Montgomery
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Abstract:
The total synthesis of aigialomycin D was carried out using a nickel-catalyzed ynal macrocyclization as a key step. This key step allowed macrocycle assembly and formation of a disubstituted alkene and a secondary hydroxyl stereocenter in a single step, although the stereocenter was formed unselectively. An interesting side reaction involving five-membered-ring synthesis by an aldehyde/styrene cyclization was observed when macrocyclization of an alkynyl silane was attempted. A mechanistic basis for this surprising process is provided.
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