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Oxidation of equimolar amounts of [p-Br[C.sub.6][H.sub.4]CNSSN]Cl and [p-[O.sub.2][NC.sub.6][H.sub.4]CNSSN]Cl with elemental [O.sub.2] in the presence of [Ph.sub.3]Sb in MeCN yields a mixture of the symmetric dithiatetrazocines, [O.sub.2]N[C.sub.6][H.sub.4]C[N.sub.4][S.sub.2]C[C.sub.6][H.sub.4]N[O.sub.2] (1) and Br[C.sub.6][H.sub.4]C[N.sub.4][S.sub.2]C[C.sub.6][H.sub.4]Br (2) as well as the unsymmetrically substituted derivative Br[C.sub.6][H.sub.4]C[N.sub.4][S.sub.2]C[C.sub.6][H.sub.4]N[O.sub.2] (3). The structures of compounds 1-3 are determined by X-ray diffraction: 1 crystallizes in the monoclinic space group [P2.sub.1]/c (a = 8.6397(4), b = 5.8359(4), c = 14.9767(11) [Angstrom], [beta] = 92.088(4)[degrees]) with half a molecule in the asymmetric unit; 2 crystallizes in the triclinic space group P1 (a = 6.5330(5), b = 8.2084(6), c = 14.7264(9) [Angstrom], [alpha] = 84.483(4)[degrees], [beta] = 77.112(4)[degrees], [gamma] = 87.879(3)[degrees]); 3 was found to crystallize in two forms: recrystallization from C[H.sub.2][Cl.sub.2] at room temperature yielded a solvent-free, triclinic phase, space group P1 (a = 6.5060(9), b = 7.0739(9), c = 9.1164(8) [Angstrom], [alpha] = 81.860(3)[degrees], [beta] = 83.406(5)[degrees], [gamma] = 66.589(5)[degrees]), whereas cooling a solution to -5[degrees]C yielded a solvated form, 3 C[H.sub.2][Cl.sub.2], which crystallizes in the monoclinic space group [P2.sub.1]/m (a = 6.179(1), b = 10.960(2), c = 13.884(3) [Angstrom], [beta] = 92.69(3)[degrees]). The N[O.sub.2] ... Br intermolecular interactions observed in the unsolvated structure of 3 are disrupted in the solvate structure; the C[H.sub.2][Cl.sub.2] molecule in the latter is aligned such that its molecular dipole interacts with both nitro and bromo groups, retaining a molecular chain motif. The structures are discussed in relation to their semi-empirically calculated molecular electrostatic potentials and calculations of intermolecular interactions using van der Waals forces combined with an electrostatic point charge model. Key words: dithiatetrazocine, crystal structure, crystal engineering, molecular electrostatic potential.

A single-crystal electron paramagnetic resonance (EPR) studies on the beta-polymorph of the organic magnet p-NCC6F4CNSSN is presented. The results revealed that the crystallographic c-axis corresponds to the intermediate axis of magnetization with the magnetic easy axis parallel to the b-axis.

Reactions of 1,10‐phenanthroline (phen) and 2‐(3,4‐dichlorophenyl)acetic acid (dcaH) with Mn(CO3) (M = LiI, NaI and MgII; n = 1 and 2) in MeOH yield the mononuclear lithium complex aqua[2‐(3,4‐dichlorophenyl)acetato‐κO](1,10‐phenanthroline‐κ2N,N′)lithium(I), [Li(C8H5Cl2O2)(C12H8N2)(H2O)] or [Li(dca)(phen)(H2O)] (1), the dinuclear sodium complex di‐μ‐aqua‐bis{[2‐(3,4‐dichlorophenyl)acetato‐κO](1,10‐phenanthroline‐κ2N,N′)sodium(I)}, [Na2(C8H5Cl2O2)2(C12H8N2)2(H2O)2] or [Na2(dca)2(phen)2(H2O)2] (2), and the one‐dimensional chain magnesium complex catena‐poly[[[diaqua(1,10‐phenanthroline‐κ2N,N′)magnesium]‐μ‐2‐(3,4‐dichlorophenyl)acetato‐κ2O:O′] 2‐(3,4‐dichlorophenyl)acetate monohydrate], {[Mg(C8H5Cl2O2)(C12H8N2)(H2O)2](C8H5Cl2O2)·H2O}n or {[Mg(dca)(phen)(H2O)2](dca)·H2O}n (3). In these complexes, phen binds via an N,N′‐chelate pocket, while the deprotonated dca− ligands coordinate either in a monodentate (in 1 and 2) or bidentate (in 3) fashion. The remaining coordination sites around the metal ions are occupied by water molecules in all three complexes. Complex 1 crystallizes in the triclinic space group P with one molecule in the asymmetric unit. The Li+ ion adopts a four‐coordinated distorted seesaw geometry comprising an [N2O2] donor set. Complex 2 crystallizes in the triclinic space group P with half a molecule in the asymmetric unit, in which the Na+ ion adopts a five‐coordinated distorted spherical square‐pyramidal geometry, with an [N2O3] donor set. Complex 3 crystallizes in the orthorhombic space group P212121, with one Mg2+ ion, one phen ligand, two dca− ligands and three water molecules in the asymmetric unit. Both dcaH ligands are deprotonated, however, one dca− anion is not coordinated, whereas the second dca− anion coordinates in a bidentate fashion bridging two Mg2+ ions, resulting in a one‐dimensional chain structure for 3. The Mg2+ ion adopts a distorted octahedral geometry, with an [N2O4] donor set. Complexes 1–3 were evaluated against urease and α‐glucosidase enzymes for their inhibition potential and were found to be inactive. Reactions of 1,10‐phenanthroline (phen) and 2‐(3,4‐dichlorophenyl)acetic acid (dcaH) with Mn(CO3) (M = LiI, NaI and MgII; n = 1 and 2) in MeOH yield the mononuclear lithium complex, the dinuclear sodium complex and the one‐dimensional chain magnesium complex. In these complexes, phen binds via an N,N′‐chelate pocket, while the deprotonated dca− ligands coordinate either in a monodentate or bidentate fashion. [ABSTRACT FROM AUTHOR]

Oxidation of equimolar amounts of [p-BrC[sub 6] H[sub 4] CNSSN]Cl and [p-O[sub 2] NC[sub 6] H[sub 4] CNSSN]Cl with elemental O[sub 2] in the presence of Ph[sub 3] Sb in MeCN yields a mixture of the symmetric dithiatetrazocines, O[sub 2] NC[sub 6] H[sub 4] CN[sub 4] S[sub 2] CC[sub 6] H[sub 4] NO[sub 2] (1) and BrC[sub 6] H[sub 4] CN[sub 4] S[sub 2] CC[sub 6] H[sub 4] Br (2) as well as the unsymmetrically substituted derivative BrC[sub 6] H[sub 4] CN[sub 4] S[sub 2] CC[sub 6] H[sub 4] NO[sub 2] (3). The structures of compounds 1–3 are determined by X-ray diffraction: 1 crystallizes in the monoclinic space group P2[sub 1] /c (a = 8.6397(4), b = 5.8359(4), c = 14.9767(11) Å, β = 92.088(4)°) with half a molecule in the asymmetric unit; 2 crystallizes in the triclinic space group P1 (a = 6.5330(5), b = 8.2084(6), c = 14.7264(9) Å, α = 84.483(4)°, β = 77.112(4)°, γ = 87.879(3)°); 3 was found to crystallize in two forms: recrystallization from CH[sub 2] Cl[sub 2] at room temperature yielded a solvent-free, triclinic phase, space group P1 (a = 6.5060(9), b = 7.0739(9), c = 9.1164(8) Å, α = 81.860(3)°, β = 83.406(5)°, γ = 66.589(5)°), whereas cooling a solution to –5°C yielded a solvated form, 3·CH[sub 2] Cl[sub 2] , which crystallizes in the monoclinic space group P2[sub 1] /m (a = 6.179(1), b = 10.960(2), c = 13.884(3) Å, β = 92.69(3)°). The NO[sub 2] ···Br intermolecular interactions observed in the unsolvated structure of 3 are disrupted in the solvate structure; the CH[sub 2] Cl[sub 2] molecule in the latter is aligned such that its molecular dipole interacts with both nitro and bromo groups, retaining a molecular chain motif. The structures are discussed in relation to their semi-empirically calculated molecular electrostatic potentials and calculations of intermolecular interactions using van der Waals forces combined with an electrostatic point charge model.Key words: dithiatetrazocine, crystal structure, crystal engineering, molecular electrostatic potential.L'oxydation de quantités équimolaires de [p-BrC[sub 6] H[sub 4] CNSSN]Cl et de [p-O[sub 2] NC[sub 6] H[sub 4] CNSSN]Cl avec de l'oxygène élémentaire, en présence de Ph[sub 3] Sb, dans du MeCN, conduit à un mélange de dithiatétrazocines symétriques, O[sub 2] NC[sub 6] H[sub 4] CN[sub 4] S[sub 2] CC[sub 6] H[sub 4] NO[sub 2] (1) et BrC[sub 6] H[sub 4] CN[sub 4] S[sub 2] CC[sub 6] H[sub 4] Br (2), aux côtés du dérivé substitué de façon non symétrique, BrC[sub 6] H[sub 4] CN[sub 4] S[sub 2] CC[sub 6] H[sub 4] NO[sub 2] (3). On a déterminé les structures des composés 1–3 par diffraction des rayons X: le composé 1 cristallise dans le groupe d'espace monoclinique P2[sub 1] /c (a = 8,6397(4), b = 5,8359(4) et c = 14,9767(11) Å, β = 92,088(4)°), avec une demi-molécule dans la maille asymétrique; 2 cristallise dans le groupe d'espace triclinique P1 (a = 6,5330(5), b = 8,2084(6) et c = 14,7264(9) Å, α = 84,483(4)°, β = 77,112(4)° et γ = 87,879(3)°); on a trouvé que 3 cristallise sous deux formes, la recristallisation dans le CH[sub 2] Cl[sub 2] , à température ambiante, conduit à des cristaux ne contenant pas de solvant, de phase triclinique et de groupe d'espace P1 (a = 6,5060(9), b = 7,0739(9) et c = 9,1164(8) Å, α = 81,860(3)°, β = 83,406(5)° et γ = 66,589(5)°) alors que le refroidissement de la solution à –5°C livre une forme solvatée, 3·CH[sub 2] Cl[sub 2] qui cristallise dans le groupe d'espace monoclinique P2[sub 1] /m (a = 6,179(1), b = 10,960(2) et c = 13,884(3) Å, β = 92,69(3)°). Les interactions intermoléculaires NO[sub 2] ···Br observées dans la structure non solvatée de 3 sont interrompues dans la structure solvatée; la molécule de CH[sub 2] Cl[sub 2] de cette dernière est alignée d'une façon telle que son dipôle moléculaire interagit à la fois avec le groupe nitro et le bromo tout en maintenant un motif de chaîne moléculaire. On discute des structures en fonction de leurs potentiels électrostatiques moléculaires calculés de façon semi-empirique et de calculs d'interactions intermoléculaires à l'aide de forces de van der Waals combinées à un modèle de charge ponctuelle électrostatique.Mots clés : dithiatétrazocine, structure cristalline, génie cristallin, potentiel électrostatique moléculaire.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Abstract: Dithiazolyl radicals with π-stacking motifs have attracted particular interest because of their ability to exhibit spin-switching between diamagnetic distorted π-stacks and paramagnetic regular π-stacked structures through a solid state phase transition. Previous studies indicate that inclusion of electronegative heteroatoms into the backbone favours lamellar structures. This methodology has been extended to the synthesis and characterisation of the title compound, 4′-cyanobenzo-1,3,2-dithiazolyl (4-NCBDTA). Its electronic structure is probed through DFT calculations, cyclic voltammetry and EPR spectroscopy and its crystal structure determined by X-ray powder diffraction at room temperature. Variable temperature SQUID magnetometry reveals that 4-NCBDTA undergoes two phase transitions, each exhibiting bistability; a high temperature phase transition occurs at room temperature (T C↓ =291K, T C↑ =304K, ΔT =13K); whilst the low temperature phase transition occurs below liquid nitrogen temperatures (T C↓ =37K, T C↑ =28K;ΔT =9K). [Copyright &y& Elsevier]

A family of substituted 1,2,4-benzothiadiazine 1-chlorides have been prepared by treatment of N -arylamidines in neat thionyl chloride at reflux. The S(iv) 1-chlorides are readily reduced under mild conditions to persistent 1,2,4-benzothiadiazinyl radicals which have been characterised by EPR spectroscopy and cyclic voltammetry. Crystallographic studies on isolated radicals indicate that the radicals dimerise via pancake bonding in the solid-state, resulting in spin-pairing and net diamagnetism., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Reactions of 1,10-phenanthroline (phen) and 2-(3,4-dichlorophenyl)acetic acid (dcaH) with M n (CO 3 ) (M = Li I , Na I and Mg II ; n = 1 and 2) in MeOH yield the mononuclear lithium complex aqua[2-(3,4-dichlorophenyl)acetato-κO](1,10-phenanthroline-κ 2 N,N')lithium(I), [Li(C 8 H 5 Cl 2 O 2 )(C 12 H 8 N 2 )(H 2 O)] or [Li(dca)(phen)(H 2 O)] (1), the dinuclear sodium complex di-μ-aqua-bis{[2-(3,4-dichlorophenyl)acetato-κO](1,10-phenanthroline-κ 2 N,N')sodium(I)}, [Na 2 (C 8 H 5 Cl 2 O 2 ) 2 (C 12 H 8 N 2 ) 2 (H 2 O) 2 ] or [Na 2 (dca) 2 (phen) 2 (H 2 O) 2 ] (2), and the one-dimensional chain magnesium complex catena-poly[[[diaqua(1,10-phenanthroline-κ 2 N,N')magnesium]-μ-2-(3,4-dichlorophenyl)acetato-κ 2 O:O'] 2-(3,4-dichlorophenyl)acetate monohydrate], {[Mg(C 8 H 5 Cl 2 O 2 )(C 12 H 8 N 2 )(H 2 O) 2 ](C 8 H 5 Cl 2 O 2 )·H 2 O} n or {[Mg(dca)(phen)(H 2 O) 2 ](dca)·H 2 O} n (3). In these complexes, phen binds via an N,N'-chelate pocket, while the deprotonated dca - ligands coordinate either in a monodentate (in 1 and 2) or bidentate (in 3) fashion. The remaining coordination sites around the metal ions are occupied by water molecules in all three complexes. Complex 1 crystallizes in the triclinic space group P-1 with one molecule in the asymmetric unit. The Li + ion adopts a four-coordinated distorted seesaw geometry comprising an [N 2 O 2 ] donor set. Complex 2 crystallizes in the triclinic space group P-1 with half a molecule in the asymmetric unit, in which the Na + ion adopts a five-coordinated distorted spherical square-pyramidal geometry, with an [N 2 O 3 ] donor set. Complex 3 crystallizes in the orthorhombic space group P2 1 2 1 2 1 , with one Mg 2+ ion, one phen ligand, two dca - ligands and three water molecules in the asymmetric unit. Both dcaH ligands are deprotonated, however, one dca - anion is not coordinated, whereas the second dca - anion coordinates in a bidentate fashion bridging two Mg 2+ ions, resulting in a one-dimensional chain structure for 3. The Mg 2+ ion adopts a distorted octahedral geometry, with an [N 2 O 4 ] donor set. Complexes 1-3 were evaluated against urease and α-glucosidase enzymes for their inhibition potential and were found to be inactive.

The dithiadiazolyl radical p-NCC6F4C6F4CNSSN* (4) retains its monomeric nature in the solid state with molecules linked together into chains via supramolecular CN-S interactions. Variable temperature magnetic studies on 4 show that it behaves as a near-ideal Curie paramagnet (|theta| less than 0.1 K), indicating negligible intermolecular exchange. The effective magnetic moment (1.78 micro(B)) is temperature independent and in excellent agreement with the value expected for an S = 1/2 paramagnet with g = 2.01(1.74 micro(B)). The lack of exchange coupling between radicals is attributed to the absence of significant orbital overlap between radical centres.