Dioxabenzosapphyrin: a new benzodifuran-derived sapphyrin analogue.
The synthesis and characterization of a new sapphyrin analogue, dioxabenzosapphyrin, are reported. The benzodifuran moiety upon which this system is based leads to the incorporation of two oxygen atoms within the central macrocyclic core, thus replacing two protonated nitrogen centers found in normal pentaaza sapphyrin derivatives, including those derived from benzodipyrroles. As expected, the loss of these two NH hydrogen bond donor sites greatly reduces the anion affinity for the diprotonated form, even though the overall charge is the same as in the corresponding sapphyrins. Interestingly, dioxabenzosapphyrin, but not the corresponding all-aza systems, is found to bind neutral guests, such as phenol and 4-nitrophenol, albeit weakly. This latter finding highlights a potentially new application for core-modified expanded porphyrin derivatives, namely, as receptors for hydrogen bond donating neutral substrates.
Cho
Dong-Gyu
DG
Department of Chemistry and Biochemistry and Institute for Cellular and Molecular Biology, The University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712-0165, USA.
Plitt
Patrick
P
Kim
Sung Kuk
SK
Lynch
Vincent
V
Hong
Seong-Jin
SJ
Lee
Chang-Hee
CH
Sessler
Jonathan L
JL
D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry; D011166:Porphyrins / Q000138:chemical synthesis* / Q000737:chemistry*
D001572:Benzofurans; D011166:Porphyrins; C531915:dioxabenzosapphyrin; C440448:sapphyrin