Novel chalcogenides of thymidine and uridine: synthesis, properties and applications
摘要:
A facile and efficient methodology has been developed for the synthesis of dithymidine and di-uridine derived disulfides using benzyltriethylammonium tetrathiomolybdate as a sulfur transfer reagent. However, a similar reaction of thymidine derivative with tetraethylammonium tetraselenotungstate as a selenium transfer reagent resulted in the formation of an unexpected cyclic diselenide. The disulfide derivatives of nucleosides have been used as precursors in a tandem disulfide cleavage-Michael addition/ring opening reactions to construct aminoacid and carbocyclic derivatives of nucleosides. (C) 2007 Elsevier Ltd. All rights reserved.
Iridium(III) and rhodium(III) cyclometalated complexes containing sulfur and selenium donor ligands
作者:Man-Kit Lau、Ka-Man Cheung、Qian-Feng Zhang、Yinglin Song、Wing-Tak Wong、Ian D. Williams、Wa-Hung Leung
DOI:10.1016/j.jorganchem.2004.04.033
日期:2004.7
[M(Buppy)2}2(μ-SCN)2] (M=Ir (10), Rh (11)), in which the SCN− ligands bind to the two metal centers in a μ-S,N fashion. Interaction of 1 and 2 with [Et4N]2[WQ4] gave trinuclear heterometallic complexes [Ir(Buppy)2}2(μ-WQ4)] (Q=S (12), Se (13)) and [Rh(Buppy)2}2(μ-WQ)4}] (Q=S (14), Se (15)), respectively. Hydrolysis of 12 led to formation of [Ir(Buppy)2}2W(O)(μ-S)2(μ3-S)}] (16) that has been characterized
te-containing heteroselenometallicclusters, [NEt4]2[(WSe4)(Et2NCS2Cu)3] 1 and [NEt4]2[(WSe4)(Me2NCS2Cu)4] 2, have been synthesized through reactions of [NEt4]2[WSe4] with CuCl and R2NCS2Na (R = Et or Me) in DMF. The [(WSe4)(Et2NCS2Cu)3]2− anion in 1 comprises three Et2NCS2Cu fragments ligated by a slightly distorted tetrahedral WSe4 moiety. The [(WSe4)(Me2NCS2Cu)4]2− anion structure in 2 possesses
Synthesis and characterization of ‘double-cubane’ complexes containing MFe3Se4 cores (MMo, W)
作者:Mark A. Greaney、Catherine L. Coyle、Robert S. Pilato、Edward I. Stiefel
DOI:10.1016/s0020-1693(00)80393-x
日期:1991.11
Abstract The reaction system (Et4N)2MSe4 (MMo, W)/FeCl3/EtSH/Na in methanol or ethanol at ambient temperature has yielded three principal products: [M2Fe6Se8(SEt)9]3−, [M2Fe7Se8(SEt)12]3− (MMo, W); and [W2Fe7Se8(SEt)12]4− which are isolable as Et4N+ salts. The structure of (Et4N)3[Mo2Fe6Se8(SEt)9] has been determined by single-crystal X-ray diffraction. It crystallizes in the hexagonal space group
hexanuclear clustercompound [(mu3-WSe4)2Ag4(mu-dppm)3] (5) was obtained from interaction of [Et4N]2[WSe4] with AgNO3 and dppm in the absence of iodide source. The above clustercompounds are electrically neutral and air-stable in both solution and the solid state and have been characterized by electronic, infrared, mass, and NMR spectroscopies. The solid-state structures of five clustercompounds have been
tetranuclear clustercompounds [(μ3-WSe4)Cu3(μ-X)(μ-L)2] [X = I, L = dppm (2a); X = Cl, L = dppa (2b)], which exhibit an open butterfly configuration. Interaction of [Et4N]2[WSe4] with [Cu(MeCN)4][PF6] and L gives the pentanuclear clustercompounds [(μ4-WSe4)Cu4(μ-L)4][PF6]2 [L = dppm (3a), dppa (3b)] which contain an open co-planar WCu4 core. The solid-state structures of clustercompounds 2a, 2b, and
[Et4N]2[WSe4] 用三核三角-双锥体铜 (I) 配合物 [Cu3(μ3-X)2(μ-L)3]X [X = I, L = 双 (二苯基膦酰基) 甲烷 (dppm) 处理 [Et4N]2[WSe4] ) (1a);X = Cl, L = 双(二苯基膦酰基)胺 (dppa) (1b)] 提供四核簇化合物 [(μ3-WSe4)Cu3(μ-X)(μ-L)2] [X = I, L = dppm (2a); X = Cl,L = dppa (2b)],呈现开蝶形结构。[Et4N]2[WSe4] 与 [Cu(MeCN)4][PF6] 和 L 的相互作用得到五核簇化合物 [(μ4-WSe4)Cu4(μ-L)4][PF6]2 [L = dppm ( 3a), dppa (3b)],其中包含一个开放的共面 WCu4 核心。簇状化合物 2a、2b 和 3a 的固态结构已通过 X 射线晶体学确定。2a 和