Affiliations: Department of Chemistry, P.O. Box 3000, FIN-90014 University of Oulu, Finland | Department of Chemistry, University of Joensuu, P.O. Box 111, FIN-80101, Joensuu, Finland
Note: [] Corresponding author. Dr. Raija Oilunkaniemi, E-mail: Raija.Oilunkaniemi@oulu.fi
Note: [] Corresponding author. Prof. Risto Laitinen, E-mail: Risto.Laitinen@oulu.fi
Abstract: The reactions of LiSeR (R = 2-thienyl, Th or 2-furyl, Fu) with PPh4Br afford isomorphic tetraphenyl (2-thienylselenolate) (1) or (2-furylselenolate) (2) in relatively good yields. In the former reaction, a small amount of (Ph4P)(SeTh) · H2O (1 · H2O) was also obtained. Both (Ph4P)(SeTh) (1) and (Ph4P)(SeFu) (2) are monoclinic, space group P21/n. The unit cell of 1 is a = 10.746(2), b = 13.353(3), c = 16.954(3) Å, β = 108.01(3)° and that of 2 is a = 10.484(2), b = 13.286(3), c = 16.900(3) Å, β = 108.13(3)°. The thienylselenolate and furylselenolate anions in 1 and 2 are located between the Ph4P+ cations and there is no association between the cations and the anions or between the anions. By contrast, in 1 · H2O (a = 8.879(2), b = 14.257(3), c = 19.883(4) Å, β = 91.84(3)°, space group P21/c) the anions are associated as dimeric units by weak hydrogen bonds between the selenium atoms of the selenolate and hydrogen atoms of two water molecules. These dimeric units form layers of skewed stacks between the Ph4P+ cations.
