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Prebiotically plausible ferrocyanide-ferricyanide photoredox cycling oxidatively converts thiourea to cyanamide, whilst HCN is reductively homologated to intermediates which either react directly with the cyanamide giving 2-aminoazoles, or have the potential to do so upon loss of HCN from the system. Thiourea itself is produced by heating ammonium thiocyanate, a product of the reaction of HCN and hydrogen sulfide under UV irradiation. This journal is

Water-soluble complexes are desirable for the aqueous detoxification of cyanide. Molybdenum complexes with α-amino acid and disulfide ligands with the formula K[(L)Mo2O2(μ-S)2(S2)] (L = leu (1), met (2), thr (3), and ser (4)) were synthesized in a reaction of [(DMF)3MoO(μ-S)2(S2)] with deprotonated α-amino acids; leu, met, thr, and ser are the carboxylate anions of l-leucine, l-methionine, l-threonine, and l-serine, respectively. Potassium salts of α-amino acids (leu (1a), met (2a), thr (3a), and ser (4a)) were prepared as precursors for complexes 1-4, respectively, by employing a nonaqueous synthesis route. The ligand exchange reaction of [Mo2O2(μ-S)2(DMF)6](I)2 with deprotonated α-amino acids afforded bis-α-amino acid complexes, [(L)2Mo2O2(μ-S)2] (6-8). A tris-α-amino acid complex, [(leu)2Mo2O2(μ-S)2(μ-leu + H)] (5; leu + H is the carboxylate anion of l-leucine with the amine protonated), formed in the reaction with leucine. 5 crystallized from methanol with a third weakly bonded leucine as a bridging bidentate carboxylate. An adduct of 8 with SCN - coordinated, 9, crystallized and was structurally characterized. Complexes 1-4 are air stable and highly water-soluble chiral molecules. Cytotoxicity studies in the A549 cell line gave IC50 values that range from 80 to 400 μM. Cyclic voltammetry traces of 1-8 show solvent-dependent irreversible electrochemical behavior. Complexes 1-4 demonstrated the ability to catalyze the reaction of thiosulfate and cyanide in vitro to exhaustively transform cyanide to thiocyanate in less than 1 h.

Described are our preliminary studies on the reactivity of thiophosphate in a setting which correlates with the cyanosulfidic systems chemistry we have previously reported. Thiophosphate adds to various nitrile groups giving the corresponding thioamides in a highly efficient manner and the mechanistic implications are briefly discussed. Thiophosphate can also act as a phosphorylating agent, which was demonstrated with adenosine. The prebiotic availability of thiophosphate must be questioned, but if a plausible synthesis can be found, the advantages it would bring to the field of prebiotic chemistry appear to be highly beneficial.

The reduction of the nitride-bridged diuranium(IV) complex Cs[{U(OSi(OtBu)3)3}2(-N)] affords the first example of a uranium nitride complex containing uranium in the +III oxidation state. Two nitride-bridged complexes containing the heterometallic fragments Cs2[UIII?-N?-UIV] and Cs3[UIII?-N?-UIII] have been crystallographically characterized. The presence of two or three Cs+ cations binding the nitride group is key for the isolation of these complexes. In spite of the fact that the nitride group is multiply bound to two uranium and two or three Cs+ cations, these complexes transfer the nitride group to CS2 to afford SCN- and uranium(IV) disulfide.

Relatively little is known about the reaction chemistry of the human defense factor hypothiocyanite (OSCN-) and its conjugate acid hypothiocyanous acid (HOSCN), in part because of their instability in aqueous solutions. Herein we report that HOSCN/OSCN- can engage in a cascade of pH- and concentration-dependent comproportionation, disproportionation, and hydrolysis reactions that control its stability in water. On the basis of reaction kinetic, spectroscopic, and chromatographic methods, a detailed mechanism is proposed for the decomposition of HOSCN/OSCN- in the range of pH 4-7 to eventually give simple inorganic anions including CN -, OCN-, SCN-, SO32-, and SO42-. Thiocyanogen ((SCN)2) is proposed to be a key intermediate in the hydrolysis; and the facile reaction of (SCN) 2 with OSCN- to give NCS(=O)SCN, a previously unknown reactive sulfur species, has been independently investigated. The mechanism of the aqueous decomposition of (SCN)2 around pH 4 is also reported. The resulting mechanistic models for the decomposition of HOSCN and (SCN) 2 address previous empirical observations, including the facts that the presence of SCN- and/or (SCN)2 decreases the stability of HOSCN/OSCN-, that radioisotopic labeling provided evidence that under physiological conditions decomposing OSCN- is not in equilibrium with (SCN)2 and SCN-, and that the hydrolysis of (SCN)2 near neutral pH does not produce OSCN-. Accordingly, we demonstrate that, during the human peroxidase-catalyzed oxidation of SCN-, (SCN)2 cannot be the precursor of the OSCN- that is produced.

The kinetics of comproportionation of hypothiocyanous acid (HOSCN) and thiocyanate (SCN-) to give thiocyanogen ((SCN)2) in acidic aqueous solutions have been determined by double-mixing stopped-flow UV spectroscopy. Hypothiocyanite (OSCN-) was generated at pH 13 by oxidation of excess SCN- with hypobromite (OBr), followed by a pH jump to acidic conditions ([H+] = 0.20-0.46 M). The observed pseudo-first-order rate constants exhibit first-order dependencies on [H +] and [SCN-] with overall third-order kinetics. The corresponding kinetics of hydrolysis of (SCN)2 have also been examined. Under conditions of high (and constant) [H+] and [SCN -], the kinetics exhibit second-order behavior with respect to [(SCN)2] and complex inverse dependences on [H+] and [SCN-]. Under conditions of low [H+] and [SCN -], the kinetics exhibit first-order behavior with respect to [(SCN)2] and independence with respect to [H+] and [SCN-]. We attribute this behavior to a shift in the rate-limiting step from disproportionation of HOSCN (second-order dependency on [(SCN) 2]) to rate-limiting hydrolysis (first-order dependency on [(SCN)2]). Thus, we have determined the following equilibrium constant by the kinetic method: (SCN)2 + H2O ? HOSCN + SCN- + H+; Khyd = [HOSCN][SCN -][H+]/[(SCN)2] = Khyd/k comp = 19.8(±0.7) s-1/ 5.14(±0.07) × 103 M-2 s-1 = 3.9 × 10-3 M2.

The phenol-based compartmental ligands of the "end-off" type, 2,6-bis{N-[2-(dimethylamino)ethyl]iminomethyl})-4-methylphenol (HL1), 2-{N-[2-(dimethylamino)ethyl]iminomethyl}-6-{N-methyl-N-[2-(dimethylamino) ethyl]aminomethyl}-4-bromophenol (HL2), 2,6-bis{2-[(2-pyridyl)ethyl]iminomethyl}-4-methylphenol (HL3) and 2-[N,N-di(2-pyridylmethyl)aminomethyl]-6-{N-[2-(dimethylamino)ethyl] iminomethyl}-4-methylphenol (HL4), have formed dinuclear zinc complexes: [Zn2(L1)(AcO)2]PF6 (1), [Zn2(L1)(NCS)3] (2), [Zn2(L2)(AcO)2]PF6 (3), [Zn2(L2)(NCS)3] (4), [Zn2(L3)-(AcO)2]PF6 (5), [Zn2(L3)(NCS)3] (6), [Zn2(L4)(AcO)2]C104 (7), [Zn2(L4)(AcO)(NCS)2] (8) and [Zn2(L4)(NCS)3] (9). The crystal structures of 1, 5·(DMF)0.5(2-PrOH)0.5, 7·CHCl3, 8·(2-PrOH) and 9·3CHCl3 have been determined. Complexes 1 and 5·(DMF)0.5(2-PrOH)0.5 have a di-μ-acetato-μ-phenolato-dizinc(II) core comprised of two square-pyramidal Zn centers. 7·CHCl3 has a similar dinuclear core, but it is comprised of one square-pyramidal Zn and one pseudo-octahedral Zn. 8·(2-PrOH) has a μ-acetato-μ-phenolato-dizinc(II) core with a unidentate thiocyanato-N group on each Zn. 9·3CHCl3 exists in two different crystals: one has a μ-thiocyanato-N-μ-phenolato-dizinc(II) core, whereas the other has a μ-phenolato-dizinc(II) core. The diacetato complexes, 1, 3, 5 and 7, are stable in solution. Hydrolytic activities of the complexes toward tris(p-nitrophenyl) phosphate (TNP) have been studied in aqueous DMF by means of UV-visible spectroscopic and 31P NMR methods. Complexes 1, 3 and 5 have an activity to hydrolyze TNP into bis(p-nitrophenyl) hydrogenphosphate (HBNP) in aqueous DMF. In contrast, 7 showed little hydrolytic activity toward TNP in aqueous DMF.

The temperature dependence of the absorption spectrum of the formation and decay of (SCN)2?-, a well-characterized dimer anion, was investigated at temperatures from 25 to 400°C. The absorption peak was found to shift to longer wavelength with temperature (red shift), from 470 nm at 25°C to 510 nm at 400°C. The equilibrium constants K1 and K2 for the reactions SCNOH?- SCN? + OH- and SCN? + SCN- ? (SCN)2?-, respectively, were found to decrease with temperature. Due to the considerable decrease of K2 with temperature, a rise in temperature shifts the reaction in favor of SCN?, so the observed yield of (SCN)2?- at high temperatures is strongly dependent on the SCN- concentration. As the SCN? concentration could be as high as or even higher than the (SCN)2?- concentration at high temperatures, a pseudo-first-order decay of SCN? has to be taken into consideration to account for the overall decay of (SCN)2?-. Using the kinetic parameters obtained in this work and available in the literature, the decay profiles of (SCN)2?- can be well reproduced for any temperature and KSCN concentration considered. A combination of the simulation and the experimental results reveals a decrease of ∈max of (SCN)2?- with temperature; the degree is ～30percent for a rise from 25 to 400°C.

The kinetics of the reaction of H2O2 with excess SCN- in acidic media was studied by use of Ti(IV) as an indicator for the concentration of H2O2. Pseudo-first-order behavior was realized by this method, and these data confirm the acid-catalyzed rate law and rate constant reported some 40 years ago for this reaction under conditions of excess H2O2. Under the same conditions except without Ti(IV), repetitive-scan spectra reveal the formation and decay of an intermediate that absorbs in the UV. In the proposed mechanism, HOSCN is produced in the first step and it is converted rapidly to (SCN)2 through its equilibrium reaction with SCN-. The observed intermediate is believed to be (SCN)2, which decays on a longer time scale. Excellent global fits of this mechanism to the repetitive-scan data are obtained with rate constants constrained by the Ti(IV) data and published previously in our study of the ClO2/SCN- reaction. These fits yield a spectrum for (SCN)2 that is characterized by λ(max) = 297 nm and ε297 = 147.M-1 cm-1, in fine agreement with our prior report.

The substitution reactions between [Re(NO)(H2O)(CN)4]2- and the nucleophiles SCN-, N3- and thiourea revealed that both the aqua and the hydroxo ligands are substituted with respective rate constants of 3.6(1) × 10-3 and 1.57(5) × 10-3 M-1 s-1 at 40°C in the case of SCN-. The pKa1 was spectrophotometrically determined as 9.90(2) at 25°C and kinetically as 9.50(4) at 40°C with NCS- as the incoming nucleophile. The (AsPh4)2[Re(NO)(SC(NH2)2)(CN) 4] complex was isolated as the product for the reaction between [Re(NO)(H2O)(CN)4]2- and thiourea and its X-ray crystal structure determined. The Re - NO and N - O bond lengths are 1.736(11) and 1.146(13) A, respectively, while the Re - S bond distance is 2.503(4) A. The thiourea is bonded cis with respect to the nitrosyl group.

Dunkin, Fehsenfeld and Ferguson have reported that the gas phase reaction between H- and N2O in a flowing afterglow instrument forms HO- and N2 with medium efficiency.The potential surface (UMP2-FC/6-311++G**//RHF/6-311++G**) for the H-/N2O system confirms this to be the predominant reaction following initial approach of H- towards the central nitrogen of N2O to form unstable intermediate -(N2O)>.The intermediate then decomposes to HO- and N2 via a deep channel.The potential surface also shows the direct formation of adducts -O-+N(H)=N- and cis HN=NO-.However these are formed with excess energy: the former converts principally into reactants, while the latter decomposes to HO- and N2. Ions having the formula 'HN2O-' may be formed in the gas phase by the reactions (i) HNO- + N2O --> HN2O- + NO, and (ii) NH2- + Me3CCH2ONO --> HN2O- + Me3CCH2OH.The product anion is stabilized by removal of some of its excess energy by the eliminated neutral.Evidence is presented which indicates that the product is either cis or trans HN=NO-, or a mixture of both .The characteristic ion molecule reaction of HN=NO- involves oxidative oxygen transfer to suitable neutral substrates.For example: HN2O- + CS2 --> HS- + N2 + COS.

The 266 nm photoelectron spectra of CN-, NCO-, and NCS- have been recorded with a pulsed time-of-flight photoelectron spectrometer.The photoelectron spectrum of CN- has also been recorded at 213 nm revealing transitions to the A 2Π state as well as the ground X 2Σ+ state of the CN radical.The following adiabatic electron affinities (EAs) are determined: EA(CN)=3.862+/-0.004 eV, EA(NCO)=3.609+/-0.005 eV, and EA(NCS)=3.537+/-0.005 eV.The adiabatic electron affinity of cyanide is in disagreement with the currently accepted literature value.Our measurement of the electron affinity of NCS confirms recent theoretical estimates that dispute the literature experimental value.By Franck-Condon analysis of the vibrational progressions observed in each spectrum, the change in bond lengths between anion and neutral are also determined.For NCO- this yields R0(C-N)=1.17+/-0.01 Angstroem and R0(C-O)=1.26+/-0.01 Angstroem, and for CN- the equilibrium bond length is found to be Re(C-N)=1.177+/-0.004 Angstroem.The gas phase fundamental for CN- is determined for the first time: ν=2035+/-40 cm-1.

Equilibria and dynamics in aqueous solutions of mixed complexes Tl(edta)X2- containing ionic medium (1 M NaClO4) have been studied by menas of 205Tl-, 15N-, 13C-, and 1H-NMR and potentiometry. Individual 205Tl chemical shifts have been determined for all the investigated complexes (X = H2O, OH, Cl, Br, CN, SCN). For the pseudohalide complexes the 15N- and 13C-NMR shifts as well as the spin-spin coupling constants J(205Tl-15N) and J(205Tl-13C) have also been determined. The coupling constant 1J(205Tl-13C) for the complex Tl(edta)CN2- is remarkably large, 10 479 Hz, indicating a very strong thallium-carbon bond. The stability constants, kX = [Tl(edta)X2-]/{[Tl(edta)-][X-]}, determined by a combination of 205Tl- and 13C-NMR and potentiometry, for X = Cl, CN, and SCN are, respectively: log KX = 2.6 (±0.1 = σ), 8.72 (±0.03) and 2.70 (±0.03). The kinetics for the X-ligand exchange was found to follow the rate equation -d[Tl(edta)X2-]/dt = kd[Tl(edta)X2-] + k2[Tl(edta)X2-][X-] which can be ascribed to the reactions Tl(edta)X2- ? kdkf Tl(edta)aq- + X- (a) Tl(edta)X2- + *X- ? k2 Tl(edta)*X2- + X- (b) where kd is ≥ 1.7 × 104, 2.7 (±0.1 = σ) × 104, 4 s-1 for X = Cl, Br, CN, and SCN, respectively, and k2 is 1.5 (±0.1) × 106 and 3.0 (±0,2) × 106 M-1 s-1, for X = CN and SCN, respectively. In order to facilitate the discussion of reaction mechanisms, the crystal and molecular structure of the compound Na2[Tl(edta)CN]·3H2O has been determined using single-crystal X-ray diffraction. This compound crystallizes in the monoclinic space group P21/c (no. 14) with a = 7.769 (2) A?, b = 14.130(6) A?, c = 17.069 (5) A?, β = 101.44 (2)°, and Z = 4. Thallium is coordinated by edta (hexadentate coordination) and cyanide; i.e., no water molecule is present in the first coordination sphere of thallium. The thallium atom is about 0.08 A? below the distorted plane of the four coordinated edta oxygens. Taking into account that the values of the formation rate constants kfX for at least X = Br and SCN are close to each other, a mechanism involving dissociation of a water molecule from the Tl(edta)aq- complex as a rate-determining step can be proposed for reaction type a. The rate constant for this step can be estimated to kw ～ 1.3 × 108 s-1 (for dissociation of one particular water molecule). A similar rate-determining step can be proposed for reaction b. In this case kw ～ 1.9·108 s-1, close to the one for reaction a and slightly higher than the corresponding value (5 × 107 s-1) for the aquated Tl3+ ion, in agreement with the expected influence of the decrease of the coordination number of thallium(III) from Tl(edta)aq- to Tlaq3+.

Rate constants for several reactions of inorganic radicals with inorganic reductants in aqueous solutions have been measured by pulse radiolysis as a function of temperature, generally between 5 and 75 deg C.The reactions studied were of the dihalide radicals, Cl2.-, Br2.-, and I2.-, the (SCN).- radical, and the neutral radical N3., reacting with the substitution-inert metal complexes, Fe(CN)6(4-), Mo(CN)8(4-), and W(CN)8(4-), and with the anions SO3(2-), HSO3(1-), NO2(1-), and ClO2(1-).The rate constants measured were in the range of 1E6 to 5E9 M-1 s-1and the calculated Arrhenius activation energies ranged from 5 to 35 kJ mol-1.The preexponential factors also varied considerably, with log A ranging from 8.9 to 13.1.The temperature dependence of the reaction rate constant is correlated to the reaction exothermicity for the metal complexes, which apparently react by outer-sphere electron transfer.The simple anions, however, have lower activation energies, which do not correlate well with the exothermicities, suggesting that these anions probably react by inner-sphere mechanism.

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By means of pulse radiolysis the one-electron reduction potentials of twelve 4-substituted phenoxy radicals have been determined. The main reference used was the ClO2./ClO2- couple. By combining the redox potentials of phenoxyl radicals with the aqueous acidities of phenols the bond strength of the phenolic O-H bond was calculated. These values were found to be in good agreement with O-H bond dissociation enthalpies measured in the gas phase.

Rate constants for the reactions of NO3 with a number of aliphatic mono- and dialkenes and monoterpenes have been determined in a 420 l reaction chamber at 1-bar total pressure of synthetic air by 298 K with a relative kinetic method.The products of these reactions have been investigated also at 1-bar total pressure of synthetic air with in situ FT-IR spectrometry and gas chromatography.In all cases, the initial formation of thermally unstable nitrooxy-peroxynitrate-type compounds containing the difunctional group -CH(OONO2)-CH(ONO2)- has been observed.The experimental results are consistent with a mechanism involving the formation of nitrooxy-alkoxy radicals, -CH(O)-CH(ONO2)-, via the self-reaction of the nitrooxy-peroxy radicals.The further reactions of the nitrooxy-alkoxy radicals then determine the final products.The main reaction pathways are (i) reaction with O2 to form nitrooxy-aldehydes or -ketones and HO2 and (II) thermal decomposition forming aldehydes/ketones and NO2.The mechanisms leading to the final products are discussed, and their possible relevance for the chemistry in the troposphere is considered.

The kinetics and mechanism of the oxidation of SCN- and I- by H atoms in acidic aqueous solution have been studied using pulse radiolysis by following the formation of (SCN)2.- and I2.-.The formation of HSCN.- has been observed as a precursor of (SCN)2.-; it has λmax = 420 nm and εmax = 4.2 x 102 m2 mol-1 and its formation rate constant k(H+SCN-) = (2.3 +/- 0.1) x 108 dm3 mol-1 s-1.Kinetic measurements are consistent with the following mechanism: where R = reduction products.With SCN- R included volatile -SH compounds (probably H2S) but not H2, and with I- R = H2.For X- = SCN-, K = 0.81 +/- 0.08 dm3 mol-1, k1 = 3.0 x 105 and k2 = 2.8 x 106 dm3 mol-1 s-1; and for X- = I-, K = 0.82 +/- 0.13 dm3 mol-1, k1 5 and k2 = (2.3 +/- 0.4) x 107 dm3 mol-1 s-1.The spectrum of HI.- could not be detected.HSCN.- reacts rapidly with O2 with a rate constant of (7.6 +/- 0.6) x 108 dm3 mol-1 s-1, but H(SCN)2.2- appears to be unreactive.No evidence for oxidation of Br- and Cl- by H could be detected.

149 transitions in the ν1 band (CN stretch) and the corresponding bending and stretching hot bands of thiocyanate (NCS-) have been measured using velocity modulation spectroscopy with a tunable diode laser.The data were fit to an effective rotation-vibration Hamiltonian, yielding spectroscopic parameters for the ( 000 ), ( 100 ) , ( 010 ) , ( 110 ) , ( 001 ), and ( 101 ) vibrational states.The band origin is ν1 = 2065.9312(13) cm-1 and the equilibrium rotational constant is calculated to be 0.197 438(61) cm-1.NCS- was prepared in a NH3/CS2 discharge, and unlike the recently studied case of NCO-, vibrational excitation in excess of the rotational temperature ( 650+/-200 K ) was not observed.

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Cyanide dispersed in the aquatic and atmospheric ecosystems represents one of the more hazardous environmental contaminants. A process is described that totally disposes of CN- by photocatalytic transformation to SCN-, a 100-fold less toxic derivative of cyanide. The method employs a Rh-loaded (0.2% by weight) CdS suspension, visible irradiation (≥405 nm or simulated AM1 solar radiation), and an alkaline aqueous sulfide medium. The quantum efficiency of the conversion process is ≥0.25.

The flowing afterglow technique has been used to study the reactions of HO2- and HCO3- in the gas phase.The hydroperoxide ion reacts slowly with CO to form HO-, and oxidizes CO2, OCS, CS2, NO, SO2, CH3NCS in fast reactions to form CO3-, CO2S-, COS2-, NO2-, SO3-, CH3NCO2-, and CH3NCOS-, respectively.Reactions of HO2- with certain amides and esters provide synthetic routes for a number of interesting peracyl anions.One of these, the peroxyformate ion, HCO3-, reacts with CO and NO in slow oxidation reactions to form the formate ion HCO2-.It also forms HCO2- upon reaction with acetone and pivalaldehyde, perhaps by Baeyer-Villiger oxidation.

The kineticas of the dissociation of the complexes L(FeT(X)4 of Fe3 with tetraphenylporphin (T) and its derivatives containing substituents X = Cl, Br, OCH3, NO2, or NH2 in the benzene ring have been investigated in proton-donating solvents as a function of the nature of the acido-ligand L = Cl-, CH3COO-, or SCN-.Conclusions have been reached about the mechanisms of the electronic influences of the functional groups and the acido-ligands on the kinetic stability of the Fe3+ complex.

The radicals Cl2(1-), Br2(1-), I2(1-), and (SCN)2(1-) were prepared by photolysis of appropriate chemical systems with one laser and were subsequently photolyzed wuth a second laser.The first three species were photolyzed at 355 nm, and (SCN)2(1-) was photolyzed at 532 nm; I2(1-) was also photolyzed at 700 nm.In each case, dissociation into the fragments X and X(1-) was detected by a bleach in the absorption of X2(1-).The quantum yield for this process is about 0.1 except for Cl2(1-) where the value is 0.2.In no case was electron photodetachment observed.Observation of the recovery of the original absorption allowed the corresponding rate constant to be measured.The values for Cl + Cl(1-) (8E9/M*s) and SCN + SCN(1-) (9E9/M*s) have not previously been measured directly.In the case of Cl2(1-) the bleach in absorption does not completely recover and the loss of absorpion is dose dependent.Because the presence of acid allows a more complete recovery it can be concluded that the product Cl atom is photolyzed by a second photon to procedure OH and Cl(1-).The quantum yield was determined to be about 0.5. this photoreaction is direct experimental evidence that the absorption band of Cl involves charge transfer from solvent.Detailed analysis of the bleaching and recovery behavior at high Cl(1-) concantrations showed no time lag which could be attributed to the 2P1/2Cl atom, implying a short lifetime for this species.

The flowing afterglow and selected ion-flow tube techniques have been used to study the reactions of H2N- with N2O, CO2, CS2, SO2, and OCS in the gas phase.Thermal energy rate coefficients and product branching ratios have been determined and are discussed in terms of detailed reaction mechanisms.With use of the SIFT-drift technique, the product distribution for the reaction of H2N- with N2O was measured as a function of the center of mass kinetic energy in the range of thermal energy to ca. 15 kcal mol1-.Qualitative studies were made of the reactions of HO-, CH3O-, and (CH3)2N- with N2O, CO2, CS2, SO2, and OCS, and the reactions of a variety of other ions with OCS were also examined.These reactions provide efficient synthetic routes for the gas-phase preparation of a variety of interesting negative ions containing nitrogen and sulfur.The basicities and heats of formation of three of these anions, H2NS-, NSO-, and NCS-, have been bracketed by proton-transfer reactions.The nucleophilicities of these three anions, as well as of H2N-, HO-, HO2-, F-, HS-, CN-, NCO-, N3-, Cl-, and Br- toward CH3I, have been measured.

The rate constants at 22°C and an ionic strength of 0.1 M for the following reactions are (Chemical Equation Presented) No adduct intermediates were detected. Formal reduction potentials for the following couples under the above conditions are as follows: Os(bpy)33+-Os(bpy)32+, 0.857 ± 0.004 V; I2-·-I-, 1.063 ± 0.011 V; I2-·I2,0.172 ± 0.011 V; (SCN)2-·-SCN-, 1.331 ± 0.008 V.