Preparation and physico-chemical studies of some chloride and alkoxide isopropoxymetallates of cobalt(II) containing {Al(OPri)4}−, {Zr2(OPri)9}− and {M(OPri)6}− Units (M = Nb or Ta)

Chloride isopropoxymetallates of cobalt(II), [ClCo{Al(OPrⁱ)₄}], [ClCo{Zr₂(OPrⁱ)₉}] and [ClCo{M(OPrⁱ)₆}] (M = Nb or Ta) have been synthesized by reactions of CoCl₂ with Li{Al(OPrⁱ)₄}, K{Zr₂(OPrⁱ)₉} and K{M(OPrⁱ)₆} in equimolar ratio. The chlorine in these chloride bimetallic isopropoxides has been replaced with alkoxide groups by their reactions with potassium alkoxides yielding products of the types, [(OR)Co{Ta(OPrⁱ)₆}] and [(OR)Co{Zr₂(OPrⁱ)₉}] (R=Me, Prⁿ, Prⁱ, Buⁿ, Bu^s or Bu^t). Alcohol interchange reactions of the above derivatives have been studied. All these new bimetallic alkoxides of cobalt(II) have been characterized by elemental analyses, IR, electronic spectral (visible) and magnetic susceptibility measurements.     

Synthesis,reactions, spectral and magnetic studies of bimetallic alkoxides of cobalt(II) with zirconium(IV)

A bimetallic isopropoxide of cobalt(II) with the formula Co[Zr₂(OPrⁱ)₉]₂, prepared by the reaction of COCl₂ with K[Zr₂(OPrⁱ)₉] in 1:2 molar ratio, has been shown to undergo alcoholysis reactions with graded alcohols (primary, secondary and tertiary) to afford products of the types, Co[Zr₂(OR)₉]₂ (where R = Me, Et, Prⁿ, Buⁿ, Buⁱ and Bu^s) Co[Zr₂(OPrⁱ)₃(OEt)₆]₂, Co[Zr₂(OPrⁱ)₆(OBu^s)₃]₂, CO[Zr₂(OPrⁱ)₃(OBu^s)₆]₂, Co[Zr₂(OPrⁱ)₆(OBu^t)₃]² and Co[Zr₂(OPrⁱ)₃(OR)₆]₂ (where R = Am^t or Bu^t). These derivatives have been characterized by elemental analyses and molecular weight determinations. Infrared, electronic (visible) spectral and magnetic susceptibility measurements suggest a distorted octahedral geometry for these derivatives.     

Synthesis and physico-chemical studies of bimetallic alkoxy derivatives of chromium(III) with niobium(V) and tantalum(V)

Reactions of CrCl₃·3thf with KM(OPrⁱ)₆ in 1:3 molar ratios in benzene yield soluble complexes of the type Cr[M(OPrⁱ)₆]₃ (M=Nb or Ta). On heating under vacuum, these complexes tend to disproportionate into Cr(OPrⁱ)₃ and M(OPrⁱ)₅ (M=Nb or Ta). A number of bimetallic alkoxides have also been synthesized by the alcoholysis of Cr[M(OPrⁱ)₆]₃ with alcohols (methanol, ethanol and t-amyl alcohol). The IR, visible, electron spin resonance and magnetic properties of these newly synthesized complexes throw light on the structural features.     

The reaction of bis(isopropylphosphino)methane with ruthenium carbonyl

Reaction of ⁱPrHPCH₂PHⁱPr with [Ru₃(CO)₁₂] in the presence of [(Ph₃P)₂N]CN catalyst gave sequentially [Ru₃(CO)₁₀(μ-ⁱPrHPCH₂PHⁱPr)] and [Ru₃- (CO)₉(μ-H)(μ₃-ⁱPrHPCH₂PⁱPr)]. The former complex exists in two isomeric forms. The structures were determined by ¹H and ³¹P NMR spectroscopy.     

Synthesis and characterisation of the halogenated azanonaboranes [(PrNH2)B8H10XNHPr] (X=Cl, Br, I) and their unexpected hydrolysis to hypho-[B5H10(μ-NHPr)]

Treatment of [(ⁱPrNH₂)B₈H₁₁NHⁱPr] with elemental halogen affords the 8-exo-halogen-substituted derivatives [(ⁱPrNH₂)B₈H₁₀XNHⁱPr] (X=Cl, Br, I). The structures of all three compounds are confirmed by NMR spectroscopy and mass spectrometry, and (for X=Br) by an X-ray diffraction study. The bromoazanonaborane undergoes hydrolytic decomposition to the new five-vertex compound [B₅H₁₀(μ-NHⁱPr)] of hypho-type structure.     

Acetoxybis(imidazolyl)methylborate [B(Im)2(OC(O)Me)Me]: Carboxylation of borane moiety of imidazolyl-based scorpionate

The acetoxy-functionalized bis(imidazolyl)borate [B(Im^N-Me)₂(OC(O)Me)Me]⁻ (=L^OAc) is synthesized by the reaction of the alkoxy precursor [B(Im^N-Me)₂(OPrⁱ)Me]⁻ (=L^OiPr) with acetic acid. In the presence of weak Brønstead acid, migration of nickel-bound acetate anion to the boron center giving L^OAc occurs. The boron-acetoxy linkage survives upon the treatment of the nickel complexes with OH⁻, although the acetoxy group on L^OAc does not coordinate to the nickel center.     

Syntheses and spectroscopic and structural characterization of silver(I) complexes containing tris(isobutyl)phosphine and poly(azol-1-yl)borates

Silver(I) derivatives [Ag(L)(PⁱBu₃)] (L = H₂B(tz)₂ (dihydrobis(1H-1,2,4-triazol-1-yl)borate), HB(tz)₃ (hydrotris(1H-1,2,4-triazol-1-yl)borate), Tp (hydrotris(1H-pyrazol-1-yl)borate), Tp∗ (hydrotris(3,5-dimethyl-1H-pyrazol-1-yl)borate), Tp^Me (hydrotris(3-methyl-1H-pyrazol-1-yl)borate), Tp^CF3 (hydrotris(3-trifluoromethyl-1H-pyrazol-1-yl)borate), Tp^4Br (hydrotris(4-bromo-1H-pyrazol-1-yl)borate), HB(btz)₃ (hydrotris(1H-1,2,4-benzotriazol-1-yl)borate), Tm (hydrotris(3-methy-1-imidazolyl-2-thione)borate), pzTp (tetrakis(1H-pyrazol-1-yl)borate), pz⁰Tp^Me (tetrakis(3-methyl-1H-pyrazol-1-yl)borate) have been synthesized from the reaction of [Ag(NO₃)(PⁱBu₃)₂] with ML (M = Na or K) and characterized both in solution (¹H- and ³¹P{¹H} NMR, ESI MS spectroscopy, conductivity) and in the solid state (IR, single crystal X-ray structure analysis). These complexes are air-stable and light-sensitive and non-electrolytes in CH₂Cl₂ and acetone in which they slowly decompose, even with the strict exclusion of oxygen and light, yielding metallic silver and/or azolate (Az) species of formula [Ag(Az)(PⁱBu₃)_x] upon breaking of the bridging B-N_(azole) bond. The solid state structures of [Ag(Tp)(PⁱBu₃)], [Ag(Tp^Me)(PⁱBu₃)], [Ag(Tp^CF3)(PⁱBu₃)], [Ag{HB(btz)₃}(PⁱBu₃)], and [Ag(Tm)(PⁱBu₃)] show that the silver atom adopts a distorted tetrahedral coordination geometry. [Ag(L)(PPh₃)] can be easily obtained from the reaction of [Ag(L)(PⁱBu₃)] with excess PPh₃, whereas from the reverse reaction of [Ag(L)(PPh₃)] with PⁱBu₃a mixture of [Ag(L)(PⁱBu₃)] and [Ag(L)]₂ and [Ag(L)(PPh₃)] was recovered. ³¹P{¹H} NMR variable temperature NMR studies showed that in the pz⁰Tp^x derivatives the scorpionate ligand acts as a bidentate donor, whereas tridentate coordination is found for all tris(azolyl)borate derivatives, both in solution and in the solid state. ESI MS data suggest the existence in solution of species such as [Ag(PⁱBu₃)₂]⁺ upon dissociation of the L ligand, and also the formation of dimeric species of the form [Ag₂(L)(PⁱBu₃)₂]⁺.     

Structural and thermal stability studies of Ti(IV) hexanuclear oxo trimethylacetato isopropoxide complex

A new titanium hexanuclear oxo carboxylato alkoxide complex, with the general formula [Ti₆O₆(OPrⁱ)₆(OOCBu^t)₆] (1), has been synthesized in a reaction of titanium isopropoxide (Ti(OPrⁱ)₄) with Bu^tCOOH in the ratio 1:1. The structure was analyzed with the elemental analysis, IR and NMR spectroscopy, and X-ray single-crystal diffraction methods. Crystal structure of 1 was solved in the trigonal centrosymmetric system . Titanium atoms form the hexanuclear cluster, where three μ₃-oxo, two μ-carboxylato bridges and the terminal alkoxide ligand, in the distorted octahedron, surround each central cation. Analysis of spectroscopic data revealed a significant nonequivalence of interactions formed by the carboxylate groups, resulting from the asymmetry of Ti-μ-OOC bonds of carboxylate bridges in the complex molecule. TGA and MS studies suggest that volatile, titanium hexanuclear species may be formed between 423 and 553 K.     

Structural characterization of zirconium isopropoxide precursors modified by di- and trichloroacetic acids

Reactions of Zr(OⁱPr)₄(PrⁱOH) with di- and trichloroacetic acid in 1:1 molar ratio in toluene gave the products Zr₂(μ-OⁱPr)₂(μ-OOCCHCl₂)(OⁱPr)₄(OOCCHCl₂)(HOⁱPr) (1) and Zr₂(μ-OⁱPr)₂(μOOCCCl₃)(OⁱPr)₄(OOCCCl₃)(HOⁱPr) (2), respectively, in quantitative yields. The molecular geometry of both (1) and (2) is constituted by a slightly distorted edge-shared bioctahedron and both have almost similar bond dimensions. Addition of dichloroacetic acid in 1:2 molar ratio to Zr(OⁱPr)₄(HOⁱPr) in toluene although yielded the bis-substituted crude product Zr(OⁱPr)₂(OOCCHCl₂)₂(HOⁱPr) (3) but its solution in toluene left for crystallization formed a tri-nuclear oxo product Zr₃(μ₃-O)(μ-OⁱPr)₂(μ-OOCCHCl₂)₃(η-OOCCHCl₂)₂(OⁱPr)₃ (3a). The three zirconium atoms in the structure of (3) are forming an isosceles triangle with a triply bridged oxo moiety at its center.     

Synthesis and characterization of some oxovanadium(V) complexes with internally functionalized oximes: Crystal and molecular structures of heptacoordinated [VO{ONC(CH3)(C4H3O-2)}3] and [VO{ONC(CH3)(C4H3S-2)}3] · 0.5C6H6

New oxovanadium(V) complexes with internally functionalized oximes of the type VO{OPrⁱ}_3−n{ONC(CH₃)(Ar)}_n] (where Ar = C₄H₃O-2, C₄H₃S-2 and C₅H₄N-2 and n = 1-3) have been prepared in quantitative yields by the reaction of VO(OPrⁱ)₃ with the corresponding oximes in various stoichiometric ratios in refluxing anhydrous benzene. The products have been characterized by elemental analyses and spectroscopic (FT IR, ¹H, ¹³C{¹H} and ⁵¹V NMR) studies. FAB mass spectral analysis of [VO{OPrⁱ}{ONC(CH₃)C₄H₃S}₂] indicates the monomeric nature of the complex. ⁵¹V NMR values for these complexes suggest the formation of tetra-coordinate species in solution. However, the single crystal X-ray diffraction studies of [VO{ONC(CH₃)(C₄H₃O-2)}₃] and [VO{ONC(CH₃)(C₄H₃S-2)}₃] · 0.5C₆H₆ exhibit the presence of vanadium(V) atoms in a unique hepta-coordination state with distorted pentagonal bipyramidal geometry in the solid state. The oxo- atom occupies the axial position while the oximato ligands are bonded in a dihapto (η²-N,O) manner with the formation of three membered rings.     

Effect of substituent dtp to optical properties of heterobimetallic M/Ag/S nest-shaped clusters (M = Mo, W)

Clusters [MoS₄Ag₃(PPh₃)₃{S₂P(OPrⁱ)₂}] (1), [WS₄Ag₃(PPh₃)₃{S₂P(OPrⁱ)₂}] (2) and [WOS₃Ag₃(PPh₃)₃{S₂P(OPrⁱ)₂}] (3) were synthesized by the reaction of (NH₄)₂MoS₄/(NH₄)₂WS₄, (NH₄)₂WOS₃ with Ag[S₂P(OPrⁱ)₂]. Their structures have been characterized by X-ray diffraction. The clusters consist of a distorted tetrahedral MS₄ (or MOS₃) (M = Mo, W) with three Ag atoms and three sulfur atom bridges (Fig. 1), and resemble roughly that of cubane-like clusters. The nonlinear optical (NLO) properties were studied with an 8 ns pulsed laser at 532 nm. Its optical response to the incident light exhibits good optical absorptive and refractive effects, with α₂ = 1.56 × 10⁻¹⁰ m W⁻¹, n₂ = 3.87 × 10⁻¹⁷ m² W⁻¹ for cluster 1; α₂ = 1.33 × 10⁻¹⁰ m W⁻¹, n₂ = 6.52 × 10⁻¹⁷ m² W⁻¹for cluster 2; and α₂ = 2.54 × 10⁻¹⁰ m W⁻¹, n₂ = 4.07 × 10⁻¹⁷ m² W⁻¹ for cluster 3 for a 1.56 × 10⁻⁴ mol dm⁻³ CH₂Cl₂ solution.     

Group 3 complexes incorporating (furyl)-substituted disilazide ligands

A series of mono- and bis-amide scandium and yttrium compounds incorporating the furyl-substituted disilazide ligand, [N{SiMe₂R}₂]⁻ {i} (where R = 2-methylfuryl) have been synthesized. The compounds Sc{i}Cl₂ (1), Sc{i}(CH₂SiMe₃)₂ (2) and Sc{i}(OAr)₂ (3) were made from suitable scandium starting materials employing either a salt metathesis protocol with Li{i} or via protonolysis of Sc-C bonds by the neutral amine H{i}. The thermally unstable bis-alkyl yttrium compound, ‘Y{i}(CH₂SiMe₃)₂^’ was isolated as the bis-THF adduct (4) and the bis-aryloxide Y{i}(OAr)₂ (5) was synthesized by elimination of LiOAr from Y(OAr)₃. The bis-amide complex Y{i}₂Cl (6) and conversion to a rare example of an yttrium benzyl compound Y{i}₂(CH₂Ph) (7) are described. The yttrium cation, [Y{i}₂]⁺, was synthesized by benzyl abstraction from 7 using B(C₆F₅)₃. Structural characterization of representative examples show variation in the coordination modes for amide ligand {i}, differing primarily in the number of furyl groups that coordinate to the metal, with examples in which zero, one or two M-O_furyl bonds are present. Preliminary investigation in two areas of catalysis are presented.     

A linear potassium metalated vanadium(IV) polymeric alkoxide: Structural and spectroscopic studies

We have been interested in the preparation of alkoxometallate “bricks” of the M′{M(OR)_n} type, with M′ = alkaline metal, M = vanadium(IV) and R = isopropyl or tert-butyl, to be employed as starting materials in salt-elimination reactions with other transition metal complexes. Here, we report the synthesis, spectroscopic characterisation and molecular structure of [{K₂(VO)₂(OPrⁱ)₆(PrⁱOH)₂}_∞] (1), prepared by a combination of Lewis acid–base and micro-hydrolysis reactions. The linear polymeric chain contains planar four-membered {(VO)₂(μ-OPrⁱ)₂} rings with vanadyl groups in anti-coplanar configuration; the rings are connected by “bridging” K(HOPrⁱ)⁺ units. Powder and solution EPR spectra suggest a spin triplet ground state, with a very weak ferromagnetic interaction between the vanadium(IV) centres at room temperature.     

Spin-spin interactions in iron(III) porphyrin radical cations with ruffled and saddled structure

Oxidation of essentially pure intermediate-spin iron(III) porphyrinates such as ruffled Fe(TⁱPrP)ClO₄ and saddled Fe(OETPP)ClO₄ produces the corresponding six-coordinate iron(III) porphyrin(por) radical cations [Fe(Por)(ClO₄)₂], where TⁱPrP and OETPP are dianions of 5,10,15,20-tetraisopropylporphyrin and 2,3,7,8,12,13,17,18-octaethyl-5,10,15,20-tetraphenylporphyrin, respectively.Spin-spin interactions in these complexes are very much different; while ruffled [Fe(TⁱPrP)(ClO₄)₂] exhibits no antiferromagnetic coupling, saddled [Fe(OETPP)(ClO₄)₂] does exhibit it. The difference in magnetic behaviors has been explained in terms of the deformation mode and electron configuration of these complexes.     

Dinitrosyl iron complexes [E5Fe(NO)2] (E = S, Se): A precursor of Roussin’s black salt [Fe4E3(NO)7]

[PPN][Se₅Fe(NO)₂] (1) and [K-18-crown-6-ether][S₅Fe(NO)₂] (2′) were synthesized and characterized by IR, UV-Vis, EPR spectroscopy, magnetic susceptibility, and X-ray structure. [PPN][Se₅Fe(NO)₂] easily undergoes ligand exchange with S₈ and (RS)₂ (R = C₇H₄SN (5), o-C₆H₄NHCOCH₃ (6), C₄H₃S (7)) to form [PPN][S₅Fe(NO)₂] and [PPN][(SR)₂Fe(NO)₂]. The reaction displays that [E₅Fe(NO)₂]⁻ (E = Se (3), S (4)) facilely converts to [Fe₄E₃(NO)₇]⁻ by adding acid HBF₄ or oxidant [Cp₂Fe][BF₄] in THF, respectively. Obviously, complexes 1 and 2′ serve as the precursors of the Roussin’s black salts 3 and 4. The electronic structure of {Fe(NO)₂}⁹ core of [Se₅Fe(NO)₂]⁻ is best described as a dynamic resonance hybrid of {Fe⁺¹(NO)₂}⁹ and {Fe⁻¹(NO⁺)₂}⁹ modulated by the coordinated ligands. The findings, EPR signal of g = 2.064 for 1 at 298 K, implicate that the low-molecular-weight DNICs and protein-bound DNICs may not exist with selenocysteine residues of proteins as ligands, since the existence of protein-bound DNICs and low-molecular-weight DNICs in vitro has been characterized with a characteristic EPR signal at g = 2.03. In addition, complex 2′ treated human erythroleukemia K562 cancer cells exposed to UV-A light greatly decreased the percentage survival of the cell cultures.     

Synthesis, characterization and X-ray crystal structures of copper(II) and nickel(II) complexes with potentially hexadentate Schiff base ligands

Copper(II) and nickel(II) complexes of potentially N₂O₄ Schiff base ligands 2-({[2-(2-{2-[(1-{2-hydroxy-5-[2-phenyl-1-diazenyl]phenyl}methylidene)amino] phenoxy}ethoxy) phenyl]imino}methyl)4-[2-phenyl-1-diazenyl]phenol (H₂L¹) and 2-({[2-(4-{2-[(1-{2-hydroxy-5-[2-phenyl-1-diazenyl]phenyl}methylidene)amino] phenoxy}butoxy) phenyl]imino}methyl)4-[2-phenyl-1-diazenyl]phenol (H₂L²) prepared of 5-phenylazo salicylaldehyde (1) and two various diamines 2-[2-(2-aminophenoxy)ethoxy]aniline (2) and 2-[4-(2-aminophenoxy)butoxy]aniline (3) were synthesized and characterized by a variety of physico-chemical techniques. The single-crystal X-ray diffractions are reported for CuL¹ and NiL². The CuL¹ complex contains copper(II) in a near square-planar environment of N₂O₂ donors. The NiL² complex contains nickel(II) in a distorted octahedral geometry coordination of N₂O₄ donors. In all complexes, H₂L¹ behaves as a tetradentate and H₂L² acts as a hexadentate ligand. Cyclic voltammetry of copper(II) complexes indicate a quasi-reversible redox wave in the negative potential range.     

Rhenium(III) and rhenium(V) complexes stabilized by the potentially tetradentate ligand tris(2-diphenylphosphinoethyl)amine

The reaction of the rhenium(V) nitrido complex [Re(N)Cl₂(PPh₃)₂] with the tripodal ligand N(CH₂CH₂PPh₂)₃ (NP₃) in THF gave [Re(N)Cl₂(η²-P,P-NP₃)] (1) in which NP₃ acts as a tridentate ligand using the nitrogen and two phosphorus donors for coordination. Refluxing 1 in a polar solvent such as ethanol produced [(η⁴-NP₃)Re(N)Cl]Cl (2) in which NP₃ acts as a tetradentate ligand. Treatment of complex [Re(O)Cl₃(AsPh₃)₂] containing the [ReO]³⁺ core with NP₃ in THF yielded [ReCl₃{η³-N,P,P-(N{CH₂CH₂Ph₂}₂{CH₂CH₂P(O)Ph₂})}] (3). Complexes 1 and 3 have been characterized by single-crystal X-ray analyses.     

Synthesis and characterisation of a series of 1,2-phenylenedioxoborylcyclopentadienyl-metal complexes [Ti(IV), Zr(IV), Hf(IV), La(III), Ce(III), Yb(III), Sn(II) and Fe(II)]

The preparation of a series of 1,2-phenylenedioxoborylcyclopentadienyl-metal complexes is described. These are of formula [M{η⁵-C₅H₄(BX)}Cl₃] [M = Ti and X = CAT (2a), CAT^t (2b) or CAT^tt (2c); X = CAT^tt and M = Zr (4a) or Hf (4b)], [M{η⁵-C₅H₄(BX)}₂Cl₂] [M = Zr, X = CAT (3a) or CAT^t (3c); or M = Hf, X = CAT (3b) or CAT^t (3d)], [M{(μ-η⁵-C₅H₃BCAT)₂ SiMe₂}Cl₂] [M = Zr (5a) or Hf (5b)], [M{η⁵-C₅H₃(BCAT)₂}Cl₃] [M = Zr (6a) or Hf (6b)], [M{η⁵-C₅H₄BCAT}₃(THF)] [M = La (7a), Ce (7b) or Yb (7c)], [Sn{η⁵-C₅ H₄(BCAT^t)}Cl](8) and [Fe{η⁵-C₅H₄(BCAT^t)}₂] (9). The abbreviations refer to BO₂C₆H₄-1,2 (BCAT) and the 4-Bu^t (BCAT^t) and the (BCAT^tt) analogues. The compounds 2a-9 have been characterised by microanalysis, multinuclear NMR and mass spectra. The single crystal X-ray structure of the lanthanum compound 7a is presented.     

Synthesis and characterization of thiolato-bridged cadmium(II) complexes with NNS-chelating thiolic ligands

Cadmium(II) complexes with 2-[(2-aminoethyl)amino]ethanethiol (HL¹), 2-[(3-aminopropyl)amino]ethanethiol (HL²), 2-[(2-pyridylmethyl)amino]ethanethiol (HL³), and 2-[[2-(2-pyridyl)ethyl]amino]ethanethiol (HL⁴), [Cd(L¹)](ClO₄) (1), [Cd(L²)](ClO₄)·1/2CH₃OH (2), [Cd{Cd(L²)₂}₂](ClO₄)₂·CH₃CON(CH₃)₂ (3a·CH₃CON(CH₃)₂), [Cd{Cd(L²)₂}₂]Cl₂·2CH₃OH (3b·2CH₃OH), [Cd{Cd(L³)₂}₂](ClO₄)₂ (4), [Cd(L⁴)](ClO₄) (5), have been synthesized and characterized by measurements of the infrared and electronic spectra. The X-ray crystal structures show that 3a and 3b have a thiolato-bridged trinuclear core with a linear arrangement of three metal atoms.     

Bis(phosphine)-Pd(II) and -Pt(II) complexes containing chiral tetrazole-thiolato rings: Synthesis, structures, and reactivity toward some electrophiles

Bis(azido)bis(phosphine)-Pd(II) and -Pt(II) complexes, [M(N₃)₂L₂] {L = PMe₃, PEt₃, PMe₂Ph, dppe = 1,2-bis(diphenylphosphino)ethane}, underwent 1,3-dipolar cycloaddition with organic chiral isothiocyanates (R^∗-NCS: R^∗ = (S)-(+)-1-phenylethyl, (R)-(−)-1-phenylethyl, (±)-1-phenylethyl, (S)-(+)-1-indanyl) to give the corresponding tetrazole-thiolato Pd(II) and Pt(II) complexes, trans-[M{S[CN₄(R^∗)]}₂L₂] or [M{S[CN₄(R^∗)]}₂(dppe)]. Spectroscopic (IR and NMR) and X-ray structural analyses of the products showed that the absolute configuration of the starting organic isothiocyanates is retained throughout the reaction. Further treatments of the isolated tetrazole-thiolato complexes with electrophiles such as HCl or benzoyl chloride produced heterocyclic compounds containing a tetrazole thione or a tetrazolyl sulfide group. In addition, organic tetrazole thiones, [S = {CN₄H(R^∗)}] containing a chiral moiety, were prepared from NaN₃ and R^∗-NCS in the presence of water.