Exploring Electrosynthesis: Bulk Electrolysis and Cyclic Voltammetry Analysis of the Shono Oxidation.

As electrochemistry continues to gain broader acceptance and use within the organic chemistry community, it is important that advanced undergraduate students are exposed to fundamental and practical knowledge of electrochemical applications for chemical synthesis. Herein, we describe the development of an undergraduate laboratory experience that introduces synthetic and analytical electrochemistry concepts to an advanced organic chemistry class. Experiments focus on the electrooxidative α-functionalization of carbamates, more generally known as the Shono oxidation, and include cyclic voltammetry analysis of two cyclic carbamates and a constant current bulk electrolysis reaction. The exercise offers students an authentic experience in organic electrochemistry, lays a practical and theoretical foundation for future engagement with concepts in electrochemistry and redox chemistry, and strengthens fundamental organic chemistry skills.

Dynamic habitat suitability modelling reveals rapid poleward distribution shift in a mobile apex predator.

Many taxa are undergoing distribution shifts in response to anthropogenic climate change. However, detecting a climate signal in mobile species is difficult due to their wide-ranging, patchy distributions, often driven by natural climate variability. For example, difficulties associated with assessing pelagic fish distributions have rendered fisheries management ill-equipped to adapt to the challenges posed by climate change, leaving pelagic species and ecosystems vulnerable. Here, we demonstrate the value of citizen science data for modelling the dynamic habitat suitability of a mobile pelagic predator (black marlin, Istiompax indica) within the south-west Pacific Ocean. The extensive spatial and temporal coverage of our occurrence data set (n = 18 717), collected at high resolution (~1.85 km(2) ), enabled identification of suitable habitat at monthly time steps over a 16-year period (1998-2013). We identified considerable monthly, seasonal and interannual variability in the extent and distribution of suitable habitat, predominately driven by chlorophyll a and sea surface height. Interannual variability correlated with El Nino Southern Oscillation (ENSO) events, with suitable habitat extending up to ~300 km further south during La Nina events. Despite the strong influence of ENSO, our model revealed a rapid poleward shift in the geometric mean of black marlin habitat, occurring at 88.2 km decade(-1) . By incorporating multiple environmental factors at monthly time steps, we were able to demonstrate a rapid distribution shift in a mobile pelagic species. Our findings suggest that the rapid velocity of climate change in the south-west Pacific Ocean is likely affecting mobile pelagic species, indicating that they may be more vulnerable to climate change than previously thought.

"My religion picked my birth control": the influence of religion on contraceptive use.

This research investigates the influence of religious preference and practice on the use of contraception. Much of earlier research examines the level of religiosity on sexual activity. This research extends this reasoning by suggesting that peer group effects create a willingness to mask the level of sexuality through the use of contraception. While it is understood that certain religions, that is, Catholicism does not condone the use of contraceptives, this research finds that Catholics are more likely to use certain methods of contraception than other religious groups. With data on contraceptive use from the Center for Disease Control's Family Growth Survey, a likelihood probability model is employed to investigate the impact religious affiliation on contraception use. Findings suggest a preference for methods that ensure non-pregnancy while preventing feelings of shame and condemnation in their religious communities.

2-(3-Bromo-4-meth-oxy-phen-yl)acetic acid.

The title compound C(9)H(9)BrO(3), was synthesized by the regioselective bromination of 4-meth-oxy-phenyl-acetic acid using bromine in acetic acid in a 84% yield. In the mol-ecular structure, the meth-oxy group is almost coplanar with the phenyl ring within 0.06 Å; the acetic acid substituent is tilted by 78.15 (7)° relative to the ring. The C-C-C angles at the OMe, acetyl and Br substituents are 118.2 (2), 118.4 (2) and 121.5 (2)°, respectively, indicating that the Br atom is electron-withdrawing, whereas the other substituents possess electron-donating properties. In the crystal, the mol-ecules form centrosymmetric strongly O-H⋯O hydrogen-bonded dimers of the type R(2) (2)(8).

Recent developments in the coordination chemistry of bis(imino)acenaphthene (BIAN) ligands with s- and p-block elements.

Bis(imino)acenaphthenes (BIAN) have been known for many years. However, it is only since the 1990s that such compounds have been recognized as robust ligands for the support of catalytically active transition metal centers. More recently, the unique stereoelectronic properties of the BIAN ligand class are beginning to be appreciated and exploited for some fascinating new developments in synthetic, structural and catalytic s- and p-block chemistry.

N,N'-Dineopentyl-naphthalene-1,8-diamine.

In the title compound, C(20)H(30)N(2), all bond distances and angles fall within the usual ranges but the C(ipso)-N distances [1.391 (5) and 1.398 (4) Å] are slightly shorter than the corresponding typical average distance of 1.42 (3) Å. The N atoms may be described as pyramidal sp(3)-hybridized with an N-H⋯H-N separation of 2.07 (2) Å. This is necessitated because the two C(bridgehead)-C(ipso)-N-C torsion angles [170.6 (4) and 172.6 (3)°] would require the amine H atoms to be in prohibitively close proximity if the N atoms were assumed to be sp(2)-hybridized.

1,4-Bis(4-bromo-2,6-diisopropyl-phen-yl)-1,4-diaza-buta-1,3-diene.

The molecule of the title compound, C(26)H(34)Br(2)N(2), lies on a crystallographic inversion center and hence the two imine groups are s-trans. The dihedral angle between the central 1,4-diaza-buta-1,3-diene unit and the attached substituted phenyl ring is 88.4 (7)°. The structure features a C-H⋯N close contact. The crystal selected for this study proved to be a non-merohedral twin with a minor component of 21.8 (3)%.

Synthesis and structure of two new (guanidinate)boron dichlorides and their attempted conversion to boron(I) derivatives.

To test the feasibility of the guanidinate architecture for the support of boron(i) carbene analogues the energy gap between the singlet and triplet states of the model compound, [Me(2)NC{N(Ph)}(2)B:] (), has been probed by both DFT and second order Møller-Plesset (MP2) methods. The singlet state is calculated to be more stable than the triplet state by between 6.0 and 10.1 kcal mol(-1). The new (guanidinate)boron dichlorides [Ph(2)NC{N(Mes)(2)]BCl(2) () and [Ph(2)NC{N(Dipp)(2)]BCl(2) () have been prepared and characterized by single-crystal X-ray diffraction. Attempts to reduce and to the corresponding boron(i) species were not successful.

Complexes of 1,2-bis(aryl-imino)acenaphthene (Ar-BIAN) ligands with some heavy p-block elements.

The new Ar-BIAN complexes [(mes-BIAN)InCl(3)(THF)] (1), [(mes-BIAN)(2)Tl][PF(6)] (2), [(dipp-BIAN)SnCl(4)] (3), [(dipp-BIAN)SbCl(3)] (4), [(dipp-BIAN)BiCl(3)] (5) and [(mes-BIAN)BiCl(3)] (6) have been prepared by treatment of the neutral mes- and dipp-substituted BIAN ligands with the p-block reagents InCl(3), TlPF(6), SnCl(4), SbCl(3), and BiCl(3). The molecular structures of complexes 1-6 have been determined by single-crystal X-ray diffraction methods. However, only the atom connectivity was established for 5.

Facile routes to alkyl-BIAN ligands.

The Alkyl-BIAN ligands tert-Butyl-BIAN and 1-Adamantyl-BIAN have been synthesized and their structures have been determined by single-crystal X-ray diffraction along with that of the ZnCl2 complex of tert-Butyl-BIAN.

Capture of phosphorus(I) and arsenic(I) moieties by a 1,2-bis(arylimino)acenaphthene (aryl-BIAN) ligand. A case of intramolecular charge transfer.

The reaction of PCl3 with SnCl2 in THF solution, followed by treatment with dpp-BIAN (dpp = 2,6-i-Pr2C6H3), affords the phosphenium complex [(dpp-BIAN)P][SnCl5.THF]. The 31P chemical shift (delta 232.5) and the metrical parameters from a single-crystal X-ray diffraction study indicate that the oxidation state of phosphorus in this compound is +3. A similar conclusion was reached regarding the phosphorus oxidation state in [(dpp-BIAN)P][I3], which was prepared via the reaction of dpp-BIAN with PI3 in CH2Cl2 solution. The arsenium salt [(dpp-BIAN)As][SnCl5.THF] was prepared by treatment of AsCl3 with SnCl2 in THF solution, followed by the addition of dpp-BIAN. The X-ray crystal structure of this salt was determined, and the pattern of bond distances and angles indicates that arsenic is present in the +3 oxidation state.

Isolation of an intermediate in the insertion of a carbodiimide into a boron-aryl bond.

A 1 : 1 Lewis acid-base complex between CyN=C=NCy and PhBCl2 has been isolated and structurally characterized, heating of which in refluxing toluene results in the amidinate, [PhC{NCy}2]BCl2; the overall reaction has been modeled by DFT calculations.

Synthetic and structural chemistry of amidinate-substituted boron halides.

The following new amidinate-substituted boron halides are reported: [PhC{N(SiMe(3))}(2)]BCl(2)(6), [MeC{NCy}(2)]BCl(2)(10), [Mes*C{NCy}(2)]BCl(2)(11), [MeC{N(i)Pr}(2)]BCl(2)(12), and [FcC{NCy}(2)]BBr(2)(13). Compound 6 was prepared via the trimethylsilyl chloride elimination reaction of BCl(3) with N,N,N'-tris(trimethylsilyl)benzamidine, and compounds 10-12 were prepared by salt metathesis between the lithium amidinates [RC(NR')(2)]Li and BX(3). Compound 13 was prepared via the insertion of 1,3-dicyclohexylcarbodiimide into the B-C bond of ferrocenyldibromoborane FcBBr(2). The molecular structures of 6, 10, 11, 13 and the known compound [PhC{N(SiMe(3))}(2)]BBr(2)(1) were established by single-crystal X-ray diffraction.

Radical reactions of a stable N-heterocyclic germylene: EPR study and DFT calculation.

The first radical adducts of a stable N-heterocyclic germylene were investigated. Novel radical species were produced from a variety of precursors and studied by EPR spectroscopy. DFT (B3LYP) calculations of radical adducts of different (C, Si, Ge) unsaturated N-heterocyclic divalent species with phenoxyl radical show that in the radicals studied the unpaired electron is delocalized over the five-membered ring and the spin density on the central atoms decreases in the following order: C > Si > Ge. These trends can be understood in terms of zwitterionic structure of radical adducts.

Unusual structural trends in the [MCl3([8]aneSe2)](M = As, Sb, Bi) adducts.

The structures of the homologous [MCl(3)([8]aneSe(2))](M = As, Sb or Bi; [8]aneSe(2)= 1,5-diselenacyclooctane) ladder structures formed from planar M(2)Cl(6) units linked by selenoether ligands with trans Se atoms reveal unexpected structural patterns--possible reasons for these are discussed.

Radical reactions of a stable N-heterocyclic silylene: EPR study and DFT calculation.

Reaction of the stable silylene, 1,3-di-tert-butyl-1,3,2-diazasilol-2-ylidene, with the free radical sources TEMPO, Hg[P(O)(OPri)2]2, (CO)3CpM-MCp(CO)3 (M = W, Mo), (CO)5Re-Re(CO)5, and toluene leads to radical adducts. The EPR spectra of these radicals indicate that the unpaired electron is delocalized over the silicon-containing five-membered ring.

Synthesis and structural features of the first thallium(I) selenoether derivatives.

The first evidence for thallium(I) complexes involving selenoether ligands is presented, together with the structure determinations for the 1D chain species [T1[MeSe(CH2)3SeMe]]PF6 and the 3D network species [T1[MeSe(CH2)2SeMe]]PF6.

Tetraaquatetrakis(trimethylphosphine oxide-kappaO)cerium(III) trichloride trihydrate.

The title compound, [Ce(C(3)H(9)OP)(4)(H(2)O)(4)]Cl(3).3H(2)O, contains eight-coordinate Ce atoms in an approximate dodecahedral arrangement, with Ce-O(P) = 2.372 (2)-2.423 (2) A and Ce-O(H(2)) = 2.518 (2)-2.630 (2) A.

Arsenic(III) halide complexes with acyclic and macrocyclic thio- and selenoether coligands: synthesis and structural properties.

The preparations of the new complexes [AsBr(3)[MeS(CH(2))(2)SMe]], [AsX(3)([9]aneS(3))] (X = Cl, Br or I; [9]aneS(3) = 1,4,7-trithiacyclononane), [AsCl(3)([14]aneS(4))] ([14]aneS(4) = 1,4,8,11-tetrathiacyclotetradecane), [AsX(3)([8]aneSe(2))] ([8]aneSe(2) = 1,5-diselenacyclooctane), [(AsX(3))(2)([16]aneSe(4))] ([16]aneSe(4) = 1,5,9,13-tetraselenacyclohexadecane), and [(AsBr(3))(2)([24]aneSe(6))] ([24]aneSe(6) = 1,5,9,13,17,21-hexaselenacyclotetracosane) are described. These are obtained from direct reaction of the appropriate AsX(3) and 1 mol equiv of the thio- or selenoether ligand in anhydrous CH(2)Cl(2) (or thf for X = I) solution. The products have been characterized by microanalysis and IR and (1)H NMR spectroscopy. In solution they are extensively dissociated, reflecting the weak Lewis acidity of AsX(3). Reaction of AsX(3) with MeSe(CH(2))(2)SeMe or MeC(CH(2)EMe)(3) (E = S or Se) gave only oils. Treatment of PCl(3) or PBr(3) with Me(2)S, MeE(CH(2))(2)EMe, or [9]aneS(3) failed to give solid complexes, and there was no evidence from NMR spectroscopy for any adduct formation in solution. The crystal structures of the first series of thioether and selenoether complexes of As(III) are described: [AsBr(3)[MeS(CH(2))(2)SMe]], C(4)H(10)AsBr(3)S(2), a = 10.2818(6) A, b = 7.8014(5) A, c = 14.503(1) A, beta = 102.9330(2) degrees, monoclinic, P2(1)/c, Z = 4; [AsI(3)[MeS(CH(2))(2)SMe]], C(4)H(10)AsI(3)S(2), a = 9.1528(1) A, b = 11.5622(2) A, c = 12.0939(2) A, beta = 93.863(1) degrees, monoclinic, P2(1)()/n, Z = 4; [AsCl(3)([9]aneS(3))], C(6)H(12)AsCl(3)S(3), a = 17.520(4) A, b = 17.520(4) A, c = 16.790(7) A, tetragonal, I4(1)cd, Z = 16; [AsCl(3)([14]aneS(4))], C(10)H(20)AsCl(3)S(4), a = 13.5942(2) A, b = 7.7007(1) A, c = 18.1270(3) A, beta = 111.1662(5) degrees, monoclinic, P2(1)()/n, Z = 4; [(AsCl(3))(2)([16]aneSe(4))], C(12)H(24)As(2)Cl(6)Se(4), a = 9.764(3) A, b = 13.164(1) A, c = 10.627(2) A, beta = 114.90(1) degrees, monoclinic, P2(1)()/n, Z = 2; [(AsBr(3))(2)([16]aneSe(4))], C(12)H(24)As(2)Br(6)Se(4), a = 10.1220(1) A, b = 13.4494(2) A, c = 10.5125(2) A, beta = 113.49(2) degrees, monoclinic, P2(1)()/n, Z = 2. [AsBr(3)[MeS(CH(2))(2)SMe]] and [AsI(3)[MeS(CH(2))(2)SMe]] reveal discrete mu(2)-halo As(2)X(6) dimeric structures involving distorted octahedral As(III), with the dithioether ligand chelating. [AsCl(3)([9]aneS(3))] adopts a discrete molecular distorted octahedral geometry with the thioether behaving as a weakly coordinated fac-capping ligand. [AsCl(3)([14]aneS(4))] forms an infinite sheet involving two mu(2)-chloro ligands on each As but bridging to two distinct As centers. Each macrocycle coordinates to two adjacent As centers via one S atom, giving a cis-octahedral Cl(4)S(2) donor set at As(III). The structures of [(AsCl(3))(2)([16]aneSe(4))] and [(AsBr(3))(2)([16]aneSe(4))] adopt 2-dimensional sheet structures with mu(2)-dihalo As(2)X(6) dimers cross-linked by mu(4)-tetraselenoether macrocycles, giving a disorted cis-X(4)Se(2) donor set at each As center. These species are compared with their antimony(III) and bismuth(III) analogues where appropriate.