Construction of new heteroselenometallic clusters: formation of crownlike [Et4N]4[(mu5-WSe4)(CuI)5(mu-I)2] and octahedral polymeric [(mu6-WSe4)Cu6I4(py)4]n from planar [Et4N]4[(mu4-WSe4)Cu4I6] with additional faces

The coplanar cluster compound [Et4N]4[(mu4-WSe4)Cu4I6] (1) was prepared from reaction of [Et4N]2[WSe4] with 4 equiv of CuI in N,N-dimethylformamide (DMF) solution in the presence of [Et(4)N]I. Treatment of 1 with pyridine (py) in dry MeCN gave the neutral cluster [(mu4-WSe4)Cu4(py)6I2] (2) in good yield. Recrystallization of 1 from py/i-PrOH resulted in the reorganization of the coplanar WSe4Cu4 core and the formation of a neutral polymeric cluster [(mu3-WOSe3)Cu3(py)3(mu-I)]n (3) containing a nest-shaped OWSe3Cu3 core and a terminal W=O bond. The interaction of cluster 1 with excess PPh3 in CH3Cl3 gave [(mu3-WSe4)Cu3(PPh3)3(mu3-I)] (4) which has a cubanelike SeWSe3Cu3I core. Treatment of 1 with 1 equiv of CuI in dimethyl sulfoxide (DMSO) yielded [Et4N]4[(mu5-WSe4)(CuI)5(mu-I)2] (5) which has a crown-like core structure. Treatment of 1 in DMF with 2 equiv of CuI in the presence of py resulted in the formation of a two-dimensional polymeric cluster, [(mu6-WSe4)Cu6I4(py)4]n (6), consisting of an octahedral WSe4Cu6 repeating unit. The solid-state structures of clusters 3, 5, and 6 have been further established by X-ray crystallography. The nonlinear optical properties of 6 have been also investigated. Cluster 6 was found to exhibit good photostability and a large optical limiting effect with the limiting threshold being ca. 0.3 J cm(-2).     

A NOVEL SYNTHESIS OF 2-SUBSTITUTED-4H-THIENO [2,3-d][1,3] OXAZIN-4-ONE AND 2,3-DISUBSTITUTED THIENO [2,3-d]PYRIMIDIN-4(3H)-ONE DERIVATIVES

Abstract

The synthesis of acetic 2-{[1-methyl-2-(4-oxo-5,6,7,8-tetrahydro-4H-benzo [4,5]-thieno [2,3-d] [1,3-oxazin-2-yl)ethylidene]amino}-4,5,6,7-tetrahydrohenzo[b]thiophene ?3-carboxylic acid anhydride 5 and 2-(oxopropyl)-5,6,7,8-tetrahydro-4H-benzo-[4,5] thieno[2,3-d][1,3]oxazin-4-one 7, has been achieved in three steps from ethyl 2-amino-4,5,6,7-tetrahydrobenzo(b]thiophene-3-carboxlate 1 via the reaction with ethyl acetoacetate followed by hydrolysis and acetic anhydride-induced cyclization. The 2-substituent in compound 5 has two functional groups i.e. active methylene and acid anhydride which are suitably located for intramolecular transformation. Thermal and/or base catalyzed intramolecular cyclization of 5 afforded 2-(4-acetoxy-(hydroxyl)-2-methyl-5,6,7,8-tetrahydrobenzo[4,5] thieno[2,3-b]pyridin-3-yl)-5,6,7,8- tetrahydro-4H-benzo[4,5]thieno[2,3-d] [1,3]oxazin-4-one 10 and 9 respectively. Treatment of 5 with hydrazine hydrate, aromatic and/or heterocyclic amines induced the same intramolecular cyclization with a concomitant oxazine-pyrimidine interconversion to give 3-amino(aryl or heteryl)-2-(4-hydroxy-5,6,7,8-tetrdhydrobenzo-[4,5]thieno[2,3-b]pyridin-3-yl)-3,4,5,6,7,8-hexahydrobenzo[4,5] thieno[2,3-d] pyrimid in-4-one 11–14 respectively.     

Monocarbaborane anion chemistry. An interesting encapsulation of the Pd2I2(P(C6H(4)-4-Me)3)4]2+ cation by a pair of [PhCB9H4I(C6H4Me)4]- anions

Reaction of the [1-Ph-closo-1-CB9H(4)-6,7,8,9,10-I5]- anion with 4-MeC6H4MgBr in the presence of [PdCl2(PPh3)2] gives the [Pd2I2(P(C6H(4)-4-Me)3)4]2+ salt of the [1-Ph-closo-1-CB9H(4)-10-I-6,7,8,9-(C6H(4)-4-Me)4]- anion, which exhibits an unusual neutral supramolecular assembly in the solid state, in which the dipalladium dication is encapsulated by two four-armed 'tetrapus' anionic units; the anion also has potentialities for four-fold dendrimer construction.     

Structural features of Ag[AuF4] and Ag[AuF6] and the stuctural relationship of Ag[AgF4]2 and Au[AuF4]2 to Ag[AuF4]2

Synchrotron radiation X-ray powder diffraction data (SPDD) have been obtained for Ag[AgF4]2, Au[AuF4]2, Ag[AuF4], and Ag[AuF6]. Ag[AgF4]2 and Au[AuF4]2 are isostructural with Ag[AuF4]2, space group (SG) P2(1)/n, Z = 2, with the following: for Ag[AgF4]2 a = 5.04664(8), b = 11.0542(2), c = 5.44914(9) A, beta = 97.170(2) degrees; for Au[AuF4]2 a = 5.203(2), b = 11.186(3), c = 5.531(2) A, beta = 90.55(2) degrees. The structure of Ag[AgF4]2 was refined successfully (SPDD) applying the Rietveld method, yielding the following interatomic distances (A): AgII-F = 2.056(12), 2.200(13), 2.558(13); AgIII-F = two at 1.846(12), others = 1.887(12), 1.909(13), 2.786-(12), 2.796(12), 2.855(12). AgAuF4, like other AA'F4 salts (A = Na-Rb; A' = Ag, Au), crystallizes in the KBrF4 structure type, SG I4/mcm (140), Z = 4 with a = 5.79109(6), c = 10.81676(7) A. SPDD gave (in A) four AuIII-F = 1.89(1) and eight AgI-F = 2.577(7). SPDD for AgAuF6 confirmed that it has the LiSbF6 structure, SG R3, Z = 3, with a = 5.2840(2), c = 15.0451(6) A.     

Mn4-硫杂杯[4]芳烃单元的溶剂导向超分子组装

以去叔丁基硫杂杯[4]芳烃与Mn(II)为研究对象,通过改变体系溶剂分别得到了两个四核化合物Mn4(T4A)2 (1)和Mn4(T4A)2(DMF)2(2) (T4A = thiacalix[4]arene)。当反应溶剂为氯仿(CHCl3)和甲醇的混合溶剂时,形成的是以四核锰为结构单元的二维“笼目”(Kagomé)状超分子化合物1,而当反应溶剂为N,N-二甲基甲酰胺(DMF)和甲醇的混合溶剂时,得到的是格子状二维超分子互穿的三维结构化合物2。化合物1具有很大的溶剂占有空隙,是一个潜在的多孔材料,而化合物2是一个紧密堆积的拓展结构。     

Synthesis of amine, halide, and pyridinium terminated 2-alkyl-p-tert-butylcalix[4]arenes

The synthesis of calix[4]arenes with functional groups tethered to a single methylene bridge has been explored. Mono-lithiated calix[4]arenes react with 1,ω-bromochloroalkanes to give 2-(ω-chloroalkyl)-calix[4]arenes, which function as key intermediates in the synthesis of a variety of tether-functionalized calix[4]arenes. Subsequent reactivity of these chloroalkyl species has allowed for successful synthesis of 2-(ω-iodoalkyl)-calix[4]arenes, 2-(ω-pyridiniumalkyl)-calix[4]arenes, and 2-(ω-aminoalkyl)-calix[4]arenes. This latter group of amine-terminated calix[4]arenes are especially significant as they may serve as useful entries to a wide range of subsequent chemistry, including metal coordination or attachment to a solid support. Both alkyl and aryl amines have been incorporated at the end of the tether, and a 2,6-diisopropylaniline derivative has been analyzed by X-ray diffraction.     

Facile synthesis of oligophenylene-substituted calix[4]arenes and their enhanced binding properties

[reaction: see text] A facile and efficient protocol for the synthesis of oligophenylene OPP(n)-substituted calix[4]arenes (with n up to 4) via iodo-substituted oligoarylcalix[4]arenes has been developed. The cooperation effect of the proximate fluoroionophores in hexylsulfanyl end-capped OPP(n)-substituted calix[4]arene assemblies leads to metal ion binding enhancement.     

Novel hetero-bimetallic metalla-macrocycles based on the bis-1-pyridyl ferrocene [Fe(eta 5-C5H(4)-1-C5H4N)2] ligand. Design,synthesis and structural characterization of the complexes [Fe(eta 5-C5H(4)-1-C5H4N)2](AgI)2(2+)/(CuII)2(4+)/(ZnII)2(4+)

The bidentate sandwich ligand [Fe(eta 5-C5H(4)-1-C5H4N)2] has been prepared, structurally characterized and employed in the preparation of the novel supramolecular heterobimetallic metalla-macrocycles [Fe(eta 5-C5H(4)-1-C5H4N)2]Ag2(NO3)(2).1.5H2O, [Fe(eta 5-C5H(4)-1-C5H4N)2]Cu2(CH3COO)(4).3H2O and [Fe(eta 5-C5H(4)-1-C5H4N)2]Zn2Cl4.     

Metallic macrocycle with a 1,3-alternate calix[4]arene phosphorus ligand

The preparation of an 1,3-alternate calix[4]arene phosphorus ligand, 25,27-bis(2-(diphenylphosphino)ethoxy)-26,28-bis(1-propyloxy)calix[4]arene (3), is presented. Ligand 3 is obtained in three steps in 64% overall yield. Reaction of 3 with [Rh(cot)2]BF4 produced the encapsulated rhodium complex [Rh[(P,P)-diphen-calix[4]arene]]BF4 (4). As revealed by a single-crystal X-ray diffraction study, the rhodium center has a bent coordination environment with a P-Rh-P angle of 135.66(3) degrees. Palladation of 3 employing [Pd(MeCN)4](BF4)2 yielded the chelate palladium complex 7 in which the palladium center has a slightly bent configuration. Treatment of the ligand with Pd(cod)Cl2 and [Pd(eta3-C4H7)(THF)2]BF4 leads to the isolation of the monometallic complex. Full characterization includes X-ray structural studies of compounds 3, 4, and 6.     

Preparation and properties of the full series of cuboidal clusters [Mo(x)W4-xSe4(H2O)12]n+ (n = 4-6) and their derivatives

Hydrothermal reactions between incomplete cuboidal cluster aqua complexes [M3Q4(H2O)9]4+ and M(CO)6 (M = Mo, W; Q = S, Se) offer easy access to the corresponding cuboidal clusters M4Q4. The complete series of homometal and mixed Mo/W clusters [Mo(x)W4-xQ4(H2O)12]n+ (x = 0-4, n = 4-6) has been prepared. Upon oxidation of the mixed-metal clusters, it is the W atom which is lost, allowing selective preparation of new trinuclear clusters [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+. The aqua complexes were converted by ligand exchange reactions into dithiophosphato and thiocyanato complexes, and crystal structures of [W4S4((EtO)2PS2)6], [MoW3S4((EtO)2PS2)6], [Mo4Se4((EtO)2PS2)6], [W4Se4((i-PrO)2PS2)6], and (NH4)6[W4Se4(NCS)12]-4H20 were determined. Cyclic voltammetry was performed on [Mo(x)W4-xCO4(H2O)12]n+, showing reversible redox waves 6+/5+ and 5+/4+. The lower oxidation states are more difficult to access as the number of W atoms increases. The [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+ species were derivatized into [Mo2WSe4(acac)3(py)3]+ and [MoW2Se4(acac)3(py)3]+, which were also studied by CV. When appropriate, the products were also characterized by FAB-MS and NMR (31P, 1H) data.     

Preparation and substitution chemistry of [Bu4N]2[W6Cl8(p-OSO2C6H4CH3)6]. A useful precursor for pseudohalide, acetate, and organometallic complexes containing the [W6Cl8](4+) core

The tosylate (p-toluenesulfonate) cluster [Bu4N]2[W6Cl8(p-OSO2C6H4CH3)6] (1) has been prepared and characterized by IR and NMR spectroscopy, elemental analysis, and an X-ray crystal structure. This cluster complex is shown to be a useful starting material for the preparation of pseudohalide clusters, [Bu4N]2[W6Cl8(NCQ)6] (Q = O (2), S (3), and Se (4)), in high yields. Cluster 1 also serves as a precursor to the new cluster compounds: [Bu4N]2[W6Cl8(O2CCH3)6] (5), [Bu4N]2[W6Cl8((mu-NC)Mn(CO)2(C5H5))6] (6), [W6Cl8((mu-NC)Ru(PPh3)2(C5H5))6][ p-OSO2C6H4CH3]4 (7), and [W6Cl8((mu-NC)Os(PPh3)2(C5H5))6][ p-OSO2C6H4CH3]4 (8). X-ray crystal structures are reported for 1, 4, and 5.     

Photoinduced [4 + 4] cycloadditions of o-quinones with oxazoles

[reaction: see text] Photocycloadditions of 9,10-phenanthraquinone (PQ) with oxazoles (1a and 1b) gave [4 + 4] products 2 with the O=C-C=O functionality in PQ and the 2-azadiene moiety in oxazole as 4pi addends. Photoreactions of 1-acetylisatin (IS) with 1a, 1c, and 1d gave [4 + 4] product A, which underwent further [2 + 2] reactions with another (3)IS to furnish 5. These regioselective and diastereoselective [4 + 4] photocycloadditions are rationalized by the intervening of the key conformers for ISC and bond formation of the most stable 1,6-diradical intermediates.     

Mo(W)/Cu/S cluster-based supramolecular arrays assembled from preformed clusters [Et4N]4[WS4Cu4I6] and [(n-Bu)4N]2[MoOS3Cu3X3] (X = I, SCN) with flexible ditopic ligands

In our working toward the rational design and synthesis of cluster-based supramolecular architectures, a set of new [WS4Cu4]- or [MoOS3Cu3]-based supramolecular assemblies have been prepared from reactions of preformed cluster compounds [Et4N]4[WS4Cu4I6] (1) and [(n-Bu)4N]2[MoOS3Cu3X3] (2, X = I; 3, X = SCN) with flexible ditopic ligands such as dipyridylsulfide (dps), dipyridyl disulfide (dpds), and their combinations with dicyanamide (dca) anion and 4,4'-bipy. The cluster precursor 1 reacted with dps or dpds and sodium dicyanamide (dca) in MeCN to produce [WS4Cu4I2(dps)3].2MeCN (4.2MeCN) and [WS4Cu4(dca)2(dpds)2].Et2O.2MeCN (5.Et2O.2MeCN), respectively. On the other hand, treatment of 2 with dpds in DMF/MeCN afforded [MoOS3Cu3I(dpds)2].0.5DMF.2(MeCN)0.5 (6.0.5DMF.2(MeCN)0.5) while reaction of 3 with sodium dicyanamide (dca) and 4,4'-bipy in DMF/MeCN gave rise to [MoOS3Cu3(dca)(4,4'-bipy)1.5].DMF.MeCN (7.DMF.MeCN). Compounds 4.2MeCN, 5.Et2O.2MeCN, 6.0.5DMF.2(MeCN)0.5, and 7.DMF.MeCN have been characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray crystallography. Compound 4 contains a 2D layer array made of the saddle-shaped [WS4Cu4] cores interlinked by three pairs of Cu-dps-Cu bridges. Compound 5 has another 2D layer structure in which the [WS4Cu4] cores are held together by four pairs of Cu-dca-Cu and Cu-dpds-Cu bridges. Compound 6 displays a 1D spiral chain structure built of the nido-like [MoOS3Cu3] cores via two pairs of Cu-dpds-Cu bridges. Compound 7 consists of a 2D staircase network in which each [MoOS3Cu3(4,4'-bipy]2 dimeric unit interconnects with four other equivalent units by a pair of 4,4'-bipy ligands and two pairs of dca anions. The [WS4Cu4] core in 4 or 5 and the [MoS3Cu3] core in 7 show a planar 4-connecting node and a seesaw-shaped 4-connecting node, respectively, which are unprecedented in cluster-based supramolecular compounds. The successful assembly of 4-7 from the three cluster precursors 1-3 through flexible ditopic ligands provides new routes to the rational design and construction of complicated cluster-based supramolecular arrays.     

Properties of 4H-[1]benzopyrano[3,4-c]-[1,2,5]-selenodiazol-4-one

4H-[1]benzopyrano[3,4-c][1,2,5]selenodiazol-4-one has been synthesized by the reaction of 3,4-diaminocoumarin with selenous acid and its reaction with several nucleophiles (alkali, ammonia, amines, hydrazine hydrate) and its nitration have been studied. Using PMR spectroscopy, a comparative kinetic study of the opening of the lactone ring in 6,8-dinitro-4H-[1]benzopyrano[3,4-c][1,2,5]seleno- and thiadiazol-4-ones has been carried out.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 128–133, January, 1991.     

A Tetranuclear Zinc(II) Complex of a [4+4] Macrocyclic Schiff Base Ligand

The cyclocondensation reaction between sodium 2,6-diformyl-4-methylphenolate(sdmp) and 1,5-diamino-3-(1-hydroxyethyl)azapentane (dhap) followed by in situ transmetallation with Zn(ClO₄)₂6H₂O produced a tetranuclear zinc(II)complex of the current biggest-sized [4+4] Schiff base macrocyclic ligand. The structure of the complex has been determined by X-ray techniques, indicating that the hydroxyethyl group of the amine, dhap, has been eliminated in the process. For comparison, the reaction of sdmp with diethylenetriamine has also been carried out. The resulting product has been characterized by its infrared and positive ion FAB mass spectra, which turned out to be a mixture of the corresponding [3+3] and [4+4] macrocyclic Schiff bases together with thecommon [2+2] mode.     

STRUCTURE STUDIES OF [Et_4N]_4[Cu_8(i-mnt)_6] (i-mnt=S_2C=C(CN)_2) AND [Me_4N]_4[Cu_5Ag_3(i-mnt)_6]·H_2O

<正> [Me4N]6[Ag6(i-mnt)6].H2O(1),[Et4N]4[Cu8(i-mnt)6](2) and [Me4N]4-[Cu5Ag3(i-mnt)6].H2O(3)(i-mnt=S2C=C(CN)2) were synthesized. The crystal and molecular structure of the complex 1 was reported by us.The structure of the complex 2 was determined from single crystal X-ray diffraction data. [Et4N]4[Cu8(i-mnt)s] 2, Mr=1870.46, monoclinic, P21/n, a=14.724(6), b = 17.228(3), c=15.59(1)A,β= 100.75(7)°,V=3886.3A3;Z = 2,Dc= 1.598 g/cm3. Complex 3 has been characterized by ICP elemental analyses and IR spectrum.     

BONDING CHARACTERISTICS OF 7-COORDINATED PENTAGONAL BIPYRAMIDAL COMPLEXES CEuCl_3(THF)_4] AND [UI_3(THF)_4]

<正> The bonding of complexes [EuCl3(THF)4] , [NdCl3(THF)4] and [UI3 (THF)4] has been studied by using SCC-DV-Xa method. It was found that THF helps to construct a polyhedral molecule and therefore considerably shortens M-X distances. The behaviour of f-orbitals in bonding was studied and discussed herein.     

Metal-free synthesis of azacalix[4]arenes

The facile preparation of N(H)-bridged azacalix[4]arenes has been achieved by stepwise nucleophilic aromatic substitutions assisted by hydrogen bonding interactions. The synthesis is uncatalyzed and affords previously unknown tetranitroazacalix[4]arenes.     

A theoretical study of the [4 + 4] dimerization of thioformylketene

[reaction and structure: see text] A theoretical study (B3LYP and G3MP2B3) of the dimerization of thioformylketene (1) was performed. Four pathways-two [4 + 2] pathways with thioformylketene (1), one [4 + 4] pathway with 1, and one [4 + 2] pathway involving 1 and thietone (11)-were considered. Interestingly, the [4 + 4] pathway with 1 had the lowest barrier (3.8 kcal/mol). The geometry of the transition state TS14 is unusual, with the forming bonds in the plane of the ketene. This suggests that the reaction is pseudopericyclic.     

Comparative study of calix[4]arene derivatives: implications for ligand design

The first comparative theoretical study of three parent calix[4]arene analogues (calix[4]arene, thiacalix[4]arene, and homooxacalix[4]arene) has been performed using molecular dynamic simulations and density functional theory (MPWB1K/6-311G^∗∗//B3LYP/6-311G^∗∗) methods. The theoretical observations herein including optimized geometry, polarity, and atomic charge data provide that homooxacalix[4]arene would offer more efficient platform for metal ion recognition compared to thiacalix[4]arene or calix[4]arene.