engleski

Control of Enantioselectivity in Rhodium(I) Catalysis by Planar Chiral Dibenzo[a, e]cyclooctatetraenes

Planar chiral 5, 11-disubstiuted dibenzo[a, e]cyclo- octatetraenes (dbCOTs) have been developed as the first useful chiral homologs to dbCOT-ligands for asymmetric applications. Methods enabling the preparation of such compounds on a gram-scale in enantiomerically pure form are described. Evaluated as ligands in rhodium(I)-catalyzed 1, 4- and 1, 2-arylation reactions, tertiary and quarternary stereogenic centers were formed with excellent yields and selectivities of up to > 99 % ee. A catalytic asymmetric synthesis of a key cyclization precursor to (À)-penifulvin A highlights the system in an applied context.

asymmetric catalysis ; cyclooctatetraenes ; fenestrenes ; planar chirality ; rhodium

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