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Authors are grateful to the Tunisian Ministry of High Education and Scientific Research for support [grant number: LR99ES14] and to the French Service for Cooperation and Cultural Action (SCAC) in Nouakchott, Mauritania for a scholarship to KE. Six new complexes of zinc(II), cadmium(II) and mercury(II) chlorides with tripyrrolidinophosphine chalcogenides of the types [MCl2(Pyrr3PE)2] (M = Zn, E = S (1) or E = Se (2); M = Cd, E = S (3) or E = Se (4)) and [{HgCl(Pyrr3PE)}2(µ-Cl)2] (E = S (5) or Se (6)) have been prepared in yields of 66-92% by reaction of the ligands with metal chloride in ethanol and characterized by 1H and 31P NMR, IR, elemental analysis, conductivity, and single crystal X-ray diffraction analysis. The results show that the complexes are pseudo-tetrahedral containing coordinated chloride ions. Interestingly, the X-ray studies reveal that while the title ligands produce dinuclear complexes with Hg, their Cd and Zn complexes are mononuclear. The tetrahedral bond angles vary from 85.69(5)° to 126.25(4)° in dinuclear complexes 5 and 6 and from 93.51(3)° to 117.38(3)° in mononuclear species 2-4. The E = S bond lengths are in the range 1.999(9)-2.198(2) Å. The coordination properties of the title ligands are discussed and compared to those obtained for their bulkier counterparts. Postprint

Twelve new zinc(II) and cadmium(II) complexes with symmetric ligands, [MCl2((R2N)3PO)2] (M = Zn, R2N = pyrrolidinyl (1), piperidinyl (2); M = Cd, R2N = pyrrolidinyl (3), piperidinyl (4)), and diffe...

Azido-copper(II) and -copper(I) complexes of 1-alkyl-2-[(o-thioalkyl)phenylazo]imidazole (SRaaiNR') have been prepared and studied. Complex 2 [Cu(SRaaiNR')(μ 1,1 -N 3 )(N 3 )] 2 dimerises via end-to-end (μ 1,3 )-N 3 to form a tetrameric structure. Azido-copper(I) complexes of the ligands are obtained as MeOH-bridged dimers, [Cu(SRaaiNR')(N 3 )(μ-OHMe)] 2 (3). The electronic spectra suggest that a small reorganisation energy (0.08 eV) is associated with the change in electronic configuration, structure and oxidation state from Cu II to Cu I . Redox interconversion, Cu II ↔ Cu I , [Cu(SMeaaiNMe)(μ-N 3 )-(N 3 )] 2 (2a) ↔ [Cu(SMeaaiNMe)(N 3 )(μ-OHCH 3 )] 2 (3a), has been performed in one case. The tetranuclear complex shows ferromagnetic and antiferromagnetic interactions. The spectra, redox chemistry and magnetism are explained by DFT studies.

The X-ray structures of dibenzo[ce]-1,2dithiine, dibenzo[ce]-1,2-dithiine-5,5-dioxide, dibenzo[ce]-1,2-dithiine-5,5,6-trioxide, and dibenzo[ce]-1, 2-dithiine-5,5,6,6-tetraoxide are reported and compared with the related "constrained" naphthalene derivatives. The S-S distances vary upon oxidation of the S centers in the order S-S SO2-S SO2-SO2 i.e. the most oxidized sulfur atoms do not lead to the longest bond lengths.

Imidazolyl and 3′-pyridyl are linked by azo bond (–NN–) to synthesize hitherto unknown mixed heterocyclic azo molecules, 2-[(3′-pyridyl)azo]imidazole (3′-PyaiH). Alkylation in presence of NaH has synthesized 1-alkyl-2-[(3′-pyridyl)azo]imidazole (3′-PyaiR′). 3′-PyaiR′ include three types of N-donor centers: N(imidazole), N(azo) and a peripheral N(pyridine). They bind to Ag+ to form 2:2 metallo-macrocycle, [Ag(3′-PyaiR′)]22+, while the reaction with Cd2+ forms Cd(3′-PyaiR′)42+. The complexes are structurally characterized by X-ray diffraction studies.

The molecular structures of naphtho[1,8-cd][1,2]dithiole, naphtho[1,8-cd][1,2]diselenole, naphtho[1,8-cd][1,2]ditellurole, naphtho[1,8-cd][1,2]dithiole I-oxide, naphtho[1,8-cd][1,2]dithiole 1,1-dioxide, and naphtho[1,8-cd][1,2]dithiole 1,1,2-trioxideand naphtho[1,8-cd][1,2]dithiole 1,1,2,2-tetroxide are compared. The E-E distance varies, broadly reflecting the degree of distortion imposed by the rigid naphthalene backbone as well as the degree of oxidation at sulfur. The naphthalene backbone imposes shortening of E-E bond lengths when E = S and Se compared to Ph-E-E-Ph systems but is itself subject to distortion as a consequence of the steric bulk of the E atoms.

Reaction of [Ru(CO)2Cl2]n with ligands Ph2P(CH2)nP(S)Ph2 (n=1(a), 2(b), 3(c), 4(d)) in 1:1 molar ratio produces complex cis-[Ru(CO)2Cl2(P∩S)](1a) (P∩S=η2-(P, S) coordinated) and cis-[Ru(CO)2Cl2(P–S)](1b–d) (P–S=η1-(P) coordinated), while 1:2 molar ratio yields complex of the type cis-[Ru(CO)2Cl2(P–S)2](2a–d). The complex 2a undergoes partial decarbonylation reaction in CH2Cl2–hexane solution to give a new chelated complex [Ru(CO)Cl(P∩S)2]Cl(2a′). Abstraction of halide with AgClO4 from the non-chelated complexes 1b–d and 2a–d afford corresponding chelated complexes [Ru(CO)2Cl(P∩S)](ClO4)(3b–d) and [Ru(CO)2(P∩S)2](ClO4)2(4a–d). The molecular structure of the complex 2a′ has been determined by single crystal X-ray diffraction. The ruthenium atom is at the centre of slightly distorted octahedral structure having the two phosphorus atoms of the two chelated P, S coordinated ligands at trans to each other, one CO group and Cl atom completing the coordination sphere. Other complexes have been characterized by elemental analysis, IR, 1H and 31P {H} NMR spectroscopy.

Silver ion assisted aquation of blue cis,trans,cis-RuCl2(RaaiR′)2 (4–6) leads to solvento species, blue–violet cis,trans,cis-[Ru(OH2)2(RaaiR′)2](ClO4)2 [RaaiR′ = p-R–C6H4–NN–C3H2–NN-1-R′ (1–3), abbreviated as N,N′-chelator where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1/4/7/10), CH2CH3(2/5/8/11), CH2Ph (3/6/9/12)] that have been reacted with NO2− in warm ethanol resulting violet dinitro complexes of the type, Ru(NO2)2(RaaiR′)2 (7–9). The structure in one case, [Ru(NO2)2(HaaiCH2Ph)2] (9a), has been established by X-ray diffraction as the cis-Ru(NO2)2 motif along with trans-N,N and cis-N′,N′ dispositions of the chelator N atoms around the coordination sphere. The nitrite complexes are useful synthons of electrophilic nitrosyls, and on triturating the compounds 7b–9b with conc. HClO4 nitro–nitrosyl derivatives, [Ru(NO2)(NO)(MeaaiR′)2](ClO4)2 (10b–12b), are isolated. The solution structure and stereoretentive transformation in each reaction step have been established by 1H NMR results. All the complexes exhibit strong MLCT transitions in the visible region. They are redox active and display one metal-centred oxidation and successive ligand-based reductions. The redox potentials of Ru(III)/Ru(II) (E1/2M) of 10b–12b are anodically shifted by ∼0.2 V as compared to those of dinitro precursors 7b–9b. The ν(NO) > 1900 cm−1 strongly suggests the presence of linear Ru–N–O bonding. The electrophilic behaviour of metal bound nitrosyl has been proved in one case (12b) by reacting with a bicyclic ketone, camphor, containing an active methylene group and an arylhydrazone with an active methine group, and the heteroleptic tris-chelates thus formed are characterised.

The synthesis and spectroscopic characterisation of three chalcogenophosphoryl ligands derived from ferrocene is reported. The synthesis was based on the oxidation of Fe[(η5-C5H4)PiPr2]2 by elementary sulfur and selenium, and hydrogen peroxide, respectively. All new compounds were characterised by X-ray crystallography and comparison with their aryl analogues was made. Contrary to Fe[(η5-C5H4)P(E)Ph2]2 (E=O, S, Se), the prepared compounds are not centrosymmetric, with the iso-propyl groups showing more flexibility than the phenyl substituents.

Unsymmetrical bidentate ligands R2P(E)-N(H)-P(E')R'(2) [R, R' = Ph, OPh, Pr-i; E, E' = O, S, Se] have been synthesised using the condensation reaction of an amino compound, R2P(E)NH2 [R = PhO, Ph; E = O, S, Se], with a phosphorus electrophile, R'P-2(E')CI [R' = Pr-i, Ph, OPh; E' = O, S, Se]. Deprotonated ligands (with (KOBu)-Bu-t) can be treated with Pd(OAC)(2) to give [Ph2P(S)-N-P(OXOPh)(2)](2)Pd, [(Pr2P)-Pr-i(S)-N-P(O)(OPh)(2)](2)Pd and [Ph2P(S)-N-P(S)(OPh)(2)](2)Pd, which show either four-membered or six-membered chelate rings. The new compounds were studied spectroscopically (NMR, IR and Raman) and by X-ray crystallography.

A novel multifunctionalised diphosphine ligand containing a P-N-Si-N-P backbone has been prepared and studied. The ligand, Ph2PN(Py)Si(Me)2N(Py)PPh2 from complexes with platinum and palladium containing six membered M-P-N-Si-N-P heterocycles. The structure, synthesis, and reactivity of these heterocycles is discussed.

The synthesis and X-Ray structure of the first six membered non-ionic genuine heterocycle is reported. The non-planar ring is formed by Cu, O, C, N, P, and S and its conformation is described as pseudo boat.

Ferrocenyl dithiadiphosphetane disulfide behaves as RPS2 in simple cycloaddition reactions. Reactions with norbornadiene, norbornene and hexamethyl dewar benzene all give rise to fused 4-membered C2PS ring compounds. Reaction with 2,3-dimethylbutadiene gave a simple Diels–Alder adduct which undergoes further reaction with BuLi and RX to yield FcP(S)(SR)(C6H9) (R = CH2Ph, o-MeC6H4CH2, 2,4-dinitrophenyl). A trithiaphosphorinane was obtained when Fc2P2S4 was reacted with benzaldehyde or trimethylacetaldehyde. Reaction of Fc2P2S4 with PhCH2N CHPh gave a dithiophospholane and a thiazadiphosphetane disulfide. The new compounds have been characterised spectroscopically with illustrative examples having been studied by X-ray crystallography.

Reaction of the title compounds (molar ratio 1:30) in refluxing toluene results in cleavage of one of the P-S-P bridges in naphthalenedithiadiphosphetanedisulphide 1 and formation of a new heterocycle 2 which contains a C3P2S ring with the phosphorus atoms substituted by OCH2CH2OH groups; reaction at 140°C results in complete desulphuration of napthalenedithiadiphosphetanedisulphide 1 and formation of the new heterocycle 1,8-naphthodiphosphonic acid anhydride 3 which contains a C3P2O ring. 2 and 3 were characterised by microanalysis, IR, 31P NMR and X-ray crystallography: 2, monoclinic, space group C2/c with a = 17.564 (4), b = 12.475 (2) and C = 16.423 (3) A, β = 102.98 (3·), calculated density 1.54 g/cm3, Z = 8, reflections collected 1089, final R value 0.0501; 3, monoclinic, space group P21/c with a = 7.961 (2), b = 8.275 (2) and c = 16.192 (5) A, β = 96.93 (3), calculated density 1.694 g/cm3, Z = 4, reflections collected 1837, final R value 0.044. No reaction occurred when 3 was heated with H2O.

The title compound, C13H14N2, was obtained from reaction of diaminonaphthalene with acetone. In both independent molecules in the asymmetric unit, the tricyclic perimidine consists of a planar (r.m.s. deviations = 0.0125 and 0.0181 Å) naphthalene ring system and an envelope conformation C4N2ringwith the NCN group hinged with respect to the naphthalene backbone by 36.9 (2) and 41.3 (2)° in the two independent molecules. The methyl substituents are arranged approximately axial and equatorial on the apical C atom. In the crystal, one of the N—H groups of one independent molecule is involved in classical N—H...N hydrogen bonding. Short intermolecular (C/N)—H...π(arene) interactions, near the short T-shaped limit, link molecules in the absence of strong acceptors.

This article belongs to the Special Issue Celebrating Two Centuries of Research in Selenium Chemistry: State of the Art and New Prospectives The synthesis and X-ray single crystal structures of a series of new 4-substituted-1,3-selenazol-2-amines is reported. The efficient preparation of 4-substituted-1,3-selenazol-2-amines was carried out by two-component cyclization of the selenoureas with equi-molar amounts of α-haloketones. The selenoureas were obtained from the reaction of Woollins’ reagent with cyanamides, followed by hydrolysis with water. All new compounds have been characterized by IR spectroscopy, multi-NMR (1H, 13C, 77Se) spectroscopy, accurate mass measurement and single crystal X-ray structure analysis. Publisher PDF

The title compound, [Fe2Ti(C5H5)4)(C10H8O2P2S4)]·3C4H8O, contains a central seven-membered TiO2P2S2ring with a very similar geometry compared to the derivative showing anisyl instead of ferrocenyl substituents, the Ti—O distance being marginally longer for the anisyl derivative. Two tetrahydrofuran solvent molecules are each disordered on a twofold axis.

Two polymorphs of 2,5-diphenyl-1,3,4-selenadiazole, C(14)H(10)N(2)Se, denoted (Ia) and (Ib), and a new polymorph of 2,5-bis(thiophen-2-yl)-1,3,4-selenadiazole, C(10)H(6)N(2)S(2)Se, (IIb), form on crystallization of the compounds, prepared using Woollins' reagent (2,4-diphenyl-1,3-diselenadiphosphetane 2,4-diselenide). These compounds, along with 2-(4-chlorophenyl)-5-phenyl-1,3,4-selenadiazole, C(14)H(9)ClN(2)Se, (III), and 2-(furan-2-yl)-5-(p-tolyl)-1,3,4-selenadiazole, C(13)H(10)N(2)OSe, (IV), show similar intermolecular interactions, with π-π stacking, C-H...π interactions and weak hydrogen bonds typically giving rise to molecular chains. However, the combination of interactions differs in each case, giving rise to different packing arrangements. In polymorph (Ib), the molecule lies across a crystallographic twofold rotation axis, and (IV) has two independent molecules in the asymmetric unit.

Funding: University of St Andrews and the Engineering and Physical Science Research Council (EPSRC, UK). The indole N-H hydrogen in the title compound, C15H12FN, does not display classical hydrogen bonding. Rather it forms an interaction with the pi system of an adjacent indole, resulting in weakly interacting chains along the [001] direction. Publisher PDF

The title molecule, C10H6O4Se2, lies on a twofold rotation axis. The Se—Se bond length of 2.305 (3) Å is similar to that in diphenyl diselenide [2.3066 (7) and 2.3073 (10) Å for the P and M isomers, respectively] and longer than that in 1,8-diselenonaphthalene [2.0879 (8) Å]. The molecule adopts a gauche conformation with respect to the C=O groups.

Both the platininum complex and the solvent mol-ecule of the title compound, [PtBr(2)(C(18)H(15)P)(2)]·CHCl(3), are located on a twofold rotation axis. The CH unit and the Cl atoms of the CHCl(3) mol-ecule are disordered over two equally occupied positions. The complex shows a trans square-planar geometry about the Pt atom.

The title compound, [Zn(C2H8N2)(3)](SiF6), was synthesized ionothermally using choline chloride-imidazolidone as solvent and template provider. In the crystal structure, the anions and cations are located on special positions of site symmetry 3.2 and show a typical octahedral geometry. The Zn-II ion is coordinated by six N atoms from three ethylenediamine molecules. The crystal structure displays weak hydrogen bonding between [SiF6](2-) anions and the ethylenediamine NH hydrogen atoms. Publisher PDF

This work is funded by EPSRC UK. In the crystal of the title compound, C10H14N2O, double supramolecular layers of PhCH2CH2CH2NHC(O)NH2 are formed parallel to the bc plane by intermolecular N-H center dot center dot center dot O hydrogen bonding, with R-2(2)(8) and R-2(1)(6) motifs in the b- and c-axis directions, respectively. The mean plane of the C-ar-C-C group makes a dihedral angle of 84.8 (2)degrees with the benzene ring. Publisher PDF

The title compound, C(10)H(8)BrN, was obtained by slow addition of sodium azide to 8-bromo-1-naphthoic acid, followed by addition of aqueous ammonia. The crude product was crystallized from petroleum ether to give pink crystals. Compared to other 1,8-disubstituted naphthalene compounds, this compound exhibits less strain between the 1 and 8 substituents. Additionally, the NH protons form both intra- and inter-molecular hydrogen bonds. The naphthalene units are arranged in a herring-bone stacking motif.

The title compound, C(23)H(19)PSe(2), has a central five-membered twist C(3)PSe ring conformation. One phenyl ring substituent, attached to an sp(2) carbon, is approximately coplanar with the C(3)PSe ring whilst the other organic substituents, attached to an sp(3)-carbon and a P(V) atom, lie on the same side of the ring.

The inorganic chemistry of sulfur is described. Oxides and oxy-anions, halides are reviewed. Keywords: sulfur; inorganic; oxides; halides; acids

C 3 HgN 3 O 2 S 2 cristallise dans P1 avec a=7,21, b=7,932, c=8,210 A, α=66,37, β=84,78, γ=64,10 o , Z=2; affinement jusqu'a R=0,041. La liaison C−S vers le soufre methyle est plus longue que la liaison analogue dans l'uree. Les liaisons C−N et N−S presentent une delocalisation considerable. Une liaison hydrogene intramoleculaire existe entre l'hydrogene de l'amine methylee et un oxygene du groupe sulfamide

The title compound, [{Au(C18H15P)}Co(C5H5)(N2S2)]ClO4, has a planar CoS2N2 ring and a close-to-linear N—Au—P angle [176.54 (11)°].

In the mol­ecule of 2-iodo­benzene­sulfonyl chloride, C6H4IO2S+·Cl−, the ortho substitution by large atoms causes angular distortions at the ring C atoms rather than significant displacement of the substituents out of the ring plane.

The title compound, [PdCl2(C3H9O3P)(2)], which is isotypic with its platinum analogue, adopts a slightly distorted cis square-planar geometry for the Pd centre. Publisher PDF

The asymmetric unit of the title compound, C12H12O5P2, contains four independent molecules, generating two dimers via pairs of intermolecular O-H center dot center dot center dot O hydrogen bonds, forming R-2(2) (8) rings. The two aryl rings of each molecule form dihedral angles of 108.6 (1), 103.2 (1), 12.5 (2) and 8.1 (2)degrees in the four molecules. Publisher PDF

This work is funded by EPSRC UK. In the title compound, NCCH2C6H4CH2CN, the bond lengths and angles are within normal ranges. The benzene ring makes dihedral angles of 4.94 (8) and 77.04 (8)degrees with the C-C-C-N mean planes. Weak non-conventional C-H center dot center dot center dot N hydrogen bonds are effective in the stabilization of the crystal structure. The weak C-H center dot center dot center dot N contacts form antiparallel chains running in the a + c direction, and ring systems with two N-atom acceptors and four H-atom donors. Publisher PDF

The title compound, [PtCl2(C8H11O2P)2], resides on a crystallographic twofold rotation axis and adopts a cis-square-planar geometry. Mol­ecules are linked by C—H⋯Cl inter­actions forming one-dimensional chains along the [010] direction.

FcP(S)S 2 P(S)Fc undergoes cycloaddition reactions with C–N bonds to generate C–P–N rings including the novel, boat shaped, PN 2 C 2 S system as well as four-membered P 2 CN rings.

Oxidative addition of the disulfide compounds naphtho[1,8-cd][1,2]dithiole, 2-tert-butylnaptho[1,8-cd][1,2]dithiole, 2,7-di-tert-butylnaphtho[1,8-cd][1,2]dithiole, 4,5-dithiaacephenanthrylene and the thio/sulfinyl and thio/sulfonyl compounds naphtho[1,8-cd][1,2]dithiole 1-oxide, and naphtho[1,8-cd][1,2]dithiole 1,1-dioxide respectively to [[Ir(mu-Cl)(cod)](2)] give dinuclear Ir-Ir bonded Ir(II) compounds [[IrCl(cod)](2)(mu(2)-1,8-S(2)-nap)] 1, [[IrCl(cod)](2)(mu(2)-1,8-S(2)-2-(t)Bu-nap)] 2, [[IrCl(cod)](2)(mu(2)-1,8-S(2)-2,7-di-(t)Bu-nap)]] 3, [[IrCl(cod)](2)(mu(2)-4,5-S(2)-phenan)] 4, [[IrCl(cod)](2)(mu(2)-1-S,8-[S(O)]-nap)] 5 and [[IrCl(cod)](2)(mu(2)-1-S,8-[S(O)(2)]-nap)] 6 where the di-sulfur ligands act as bridges between the two Ir(II) metal centres. The compounds were obtained in moderate to good yields as orange or deep red powders or crystalline solids. Five of the new complexes have been structurally characterised and were found to have Ir-Ir bond lengths in the range 2.7630(8) to 2.8113(11) A.