Preparation and Structure of Two Ditungsten Compounds Synthesized with the 3,5-Dichlorophenylformamidinate Ligand.
The structure, preparation, and spectroscopy of a W(2)(II, II) paddlewheel complex with four formamidinate ligands is reported. Upon exposure to air and moisture in solution, the W(2)(II, II) core undergoes an oxidative addition reaction to form a W(2)(III, III) edge-sharing bioctahedral (ESBO) complex with two bridging hydroxides. The products, W(2)(&mgr;-DCPF)(4) (1) and W(2)(&mgr;-OH)(2)(&mgr;-DCPF)(2)(eta(2)-DCPF)(2) (2) where DCPF is [(3,5-Cl(2)C(6)H(3))NC(H)N(3,5-Cl(2)C(6)H(3))(-)], were characterized by UV-vis and (1)H NMR spectroscopy. Structural data are presented for W(2)(&mgr;-DCPF)(4) with four bridging formamidinate ligands and W(2)(&mgr;-OH)(2)(&mgr;-DCPF)(2)(eta(2)-DCPF)(2) with the formamidinate ligands in both chelating and bridging positions. Crystallographic data for W(2)(&mgr;-DCPF)(4) (1) and W(2)(&mgr;-OH)(2)(&mgr;-DCPF)(2)(eta(2)-DCPF)(2) (2) are as follows: (1), C(68)H(60)Cl(16)N(8)O(4)W(2), a = 12.6906(3) Å, b = 12.7818(4) Å, c = 13.0450(3) Å, alpha = 109.173(1) degrees, beta = 93.865(1) degrees, gamma = 103.746(1) degrees, triclinic, P&onemacr; (No. 2), and Z = 1 and (2), C(59)H(35)Cl(16)N(8)O(2)W(2), a = 17.1524(1) Å, b = 20.6568(3) Å, c = 19.3959(3) Å, beta = 102.791(1) degrees, monoclinic, C2/c (No. 15), and Z = 4.
Carlson-Day
Kathryn M.
KM
Department of Chemistry, Harvard University, Cambridge, Massachusetts 02138.
Eglin
Judith L.
JL
Smith
Laura T.
LT
Staples
Richard J.
RJ