Organometallic Selenolates. 5.(1) Synthesis and Complexing Properties of 2-Propene- and 2-Methyl-2-propeneselenolato Molybdenum and Tungsten Compounds. Crystal Structures of cp(CO)(3)WSeCH(2)C(CH(3))=CH(2), [cp(CO)(2)MoSeCH(2)C(CH(3))=CH(2)](2), [cp(CO)(3)Mo(&mgr;-SeCH(2)C(CH(3))=CH(2))W(CO)(5)], [cp(CO)(3)Mo(&mgr;-SeCH(2)C(CH(3))=CH(2))Mo(CO)(5)], and [cp(CO)(3)Mo(&mgr;-SeCH(2)CH=CH(2))Mo(CO)(5)].
2-Propene- and 2-methyl-2-propeneselenolato complexes of molybdenum(II) and tungsten(II) have been prepared via insertion of gray selenium into alkali-metal-molybdenum and -tungsten bonds and subsequent reaction with allyl and beta-methallyl chlorides. The complexes are monomeric in the solid state. The (beta-methallyl)molybdenum compound cp(CO)(3)MoSeCH(2)C(CH(3))=CH(2) (2) decomposes slowly in solution with CO loss and formation of the corresponding dimer [cp(CO)(2)MoSeCH(2)C(CH(3))=CH(2)](2) (3), whose crystal structure has been determined (C(22)H(24)Mo(2)O(4)Se(2), monoclinic, P2(1)/c, a = 11.151(2) Å, b = 13.436(3) Å, c = 16.872(3) Å, beta = 102.42(2) degrees, Z = 4). A monomeric structure has been found for cp(CO)(3)WSeCH(2)C(CH(3))=CH(2) (5) (C(12)H(12)O(3)SeW, triclinic, P&onemacr;, a = 7.592(3) Å, b = 7.700(3) Å, c = 12.296(5) Å, alpha = 98.31(4) degrees, beta = 104.24(2) degrees, gamma = 108.49(3) degrees, Z = 2). Additionally, the complexing properties of the selenolato complexes have been investigated. The reactions of the molybdenum complexes cp(CO)(3)MoSeCH(2)CH=CH(2) (1) and (2) with the metal(0)-carbonyl complexes W(CO)(5)(THF), (CH(3)CN)(3)Mo(CO)(3), and (eta(6)-C(7)H(8))Mo(CO)(3) (C(7)H(8) = cycloheptatriene) led to the formation of [cp(CO)(3)Mo(&mgr;-SeCH(2)C(CH(3))=CH(2))M(CO)(5)] (M = W (6), Mo (7)) and [cp(CO)(3)Mo(&mgr;-SeCH(2)CH=CH(2))Mo(CO)(5)] (8), respectively. 6 and 7 are isostructural and crystallize in the monoclinic space group P2(1)/n (6, C(17)H(12)MoO(8)SeW, a = 14.708(2) Å, b = 9.837(2) Å, c = 14.958(2) Å, beta = 103.030(10) degrees, Z = 4; 7, C(17)H(12)Mo(2)O(8)Se, a = 14.712(2) Å, b = 9.8670(10) Å, c = 14.982(2) Å, beta = 103.100(10) degrees, Z = 4), whereas [cp(CO)(3)Mo(&mgr;-SeCH(2)CH=CH(2))Mo(CO)(5)] (8) crystallizes in the noncentrosymmetric orthorhombic space group Pna2(1) (C(16)H(10)Mo(2)O(8)Se, a = 18.638(4) Å, b = 9.707(2) Å, c = 11.169(3) Å, Z = 4). Furthermore, (77)Se-NMR spectra displayed chemical shifts consistent with earlier results on related complexes.
Jones
Peter G.
PG
Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Postfach 3329, 38023 Braunschweig, Germany.
Laube
Jörg
J
Thöne
Carsten
C