Stepwise Boron-to-Zinc C6F5 Group Transfer in a Zn−Calixarene System
datasetposted on 09.02.2009, 00:00 by Natalie Kotzen, Israel Goldberg, Arkadi Vigalok
Methylzinc calixarene complex (1) reacts with one equivalent of B(C6F5)3 to give the ion-pair (calixarene)Znδ+−Me−B(C6F5)3δ− complex (2), which readily undergoes the pentafluorophenyl group transfer to the zinc center. Reaction between 1 and H2O−B(C6F5)3 results in the formation of the ion-pair (calixarene)Znδ+−HO−B(C6F5)3δ− complex (4). In contrast to 2, complex 4 requires harsher reaction conditions to undergo the C6F5 group transfer, with the reaction taking place under the autocatalytic conditions.