Über Chalkogenolate. 144. Darstellung und Eigenschaften von Alkalimetall-t-butyl-carbonaten,Neue Untersuchungen über Trimethylsilylcarbonate

On Chalcogenolates. 144. Synthesis and Properties of Alkali Metal t-Butyl Carbonates. Reinvestigations of Trimethylsilyl Carbonates The t-butyl carbonates M[O₂C? OC(CH₃)₃], where M = Li, Na, K, Rb, Cs, have been prepared by reaction of the corresponding t-butoxide with CO₂ and characterized by means of diverse methods. The equivalent conductivities of the [O₂C? OC(CH₃)₃]^? ion in aqueous solution have been determined and the Stokes radius, the radius of the hydrated ion, and the diffusion coefficient were calculated. The dissociation constant of t-butyl carbonic acid in water at 25°C is K_a = (1.63 ± 0.03)· 10^?8. The thermodynamic data of dissociation were calculated. New data of trimethylsilyl carbonates [O₂C? OSi(CH₃)₃]^? are given.     

Über Chalkogenolate. 89. Untersuchungen über N-Dicyandithiocarbamidsäure Darstellung und Eigenschaften der freien Säure

On Chalcogenolates. 89. Studies on N-Dicyandithiocarbamic Acid. Preparation and Properties of the Free Acid Colorless N-dicyandithiocarbamic acid (melting point: 112°C) has been prepared by reaction between a suspension of K[S₂C? N(CN)₂] in diethyl ether and a solution of HCl in (C₂H₅)₂O at 0°C; the ether was distilled off at 0°C in vacuo. The compound has been characterized by means of infared spectra, electron absorption spectra, ¹H-NMR spectra, and mass spectra. The dissociation constant of N-dicyandithiocarbamic acid in water is K_a = (1.69 ± 0.1) X 10^?1 20°C. The thermodynamic data of the dissociation were calculated.     

Gleichgewichte der Protonenaddition an 1, 1-Bis-(4′, 4″-dimethylaminophenyl)-äthylen in Methanol und in Dimethylsulfoxid

The first and second proton addition equilibrium constants of 1,1-bis-(4′, 4″-dimethylaminophenyl)-ethylene ( 1 ) have been measured by the spectrophotometric method in methanol and in dimethylsulfoxide. Defined as acid dissociation constants of the mono- and diprotonated adduct they are: K₁ (CH₃OH) = 8.3 (± 0.9) · 10^?6M, K₂ (CH₃OH) = 1.22 (± 0.06) · 10^?4M, K₁ (DMSO) = 2.3 (± 0.9) · 10^?3M, K₂ (DMSO) ≥ 1M. The evaluation of the electronic and the NMR. spectra demonstrates that the equilibrium of the two monoprotonated tautomers 2 (methyl-carbenium ion) and 3 (ammonium ion) is, in methanol to about 96% on the side of the ammonium ion (tautomeric equilibrium constant K₂₃ = [3]/[2] ? 23). The tautomer 2 cannot be detected in dimethylsulfoxide. The possible causes of these solvent effects are discussed.     

Über Chalkogenolate. 151. Untersuchungen über Derivate der N-Thioformyldithiocarbamidsäure. 1. Darstellung und Eigenschaften von N-Thioformyldithiocarbamaten

On Chalcogenolates. 151. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 1. Synthesis and Properties of N-Thioformyl Dithiocarbamates The N-thioformyl dithiocarbamates M[S₂C? NH? CS? H], where M = K, Rb, Cs, Tl, NH₄, [N(ⁿC₄H₉)₄], Na[S₂C? NH? CS? H] · 0.5 H₂O, and Ba[S₂C? NH? CS? H]₂ · 3 HO? CH₂? CH₂? OCH₃ have been prepared by use of partial different procedures. The compounds were characterized with chemical and thermal methods as well as by means of electron absorption, infrared, nuclear magnetic resonance (¹H and ¹³C), and mass spectra. Attempts to synthesize N-thioformyl dithiocarbamic acid were not successful.     

Über Chalkogenolate. 145. Trimethylgermanyl- und Trimethylstannylcarbonate

On Chalcogenolates. 145. Trimethylgermyl and Trimethylstannyl Carbonates The hitherto unknown salts of the hemiesters of carbonic acid Li[O₂C? OGe(CH₃)₃] and Li[O₂C? OSn(CH₃)₃] have been prepared by reaction of Li[OGe(CH₃)₃] and Li[OSn(CH₃)₃], respectively, with CO₂ at 0°C. Both compounds were characterized by means of diverse spectoscopic methods.     

Über μ-Carboxylato-μ-hydroxo-bis(triamminkobalt(III))-Komplexe

Report of the preparation, chemical properties, and the infrared-to-ultra-violet spectra of the perchlorates and bromides of the two complex cations [Co₂{ac(OH)₂}(NH₃)₆]³⁺ (where ac = HCO₂, CH₃CO₂; CH₂ClCO₂, CHCl₂CO₂, CCl₃CO₂, CHFCO₂, CHF₂CO₂ und CF₃CO₂) and [Co₂{ac₂(OH)}(NH₃)₆]³⁺ (where ac = CH₂ClCO₂, CHClCO₂ und CCl₃CO₂). The perchlorate, nitrate, bromide and dithionate salts of the tetranuclear complex [Co₄{C₂O₄(OH)₄}(NH₃)₁₂]⁶⁺ are described. The complex reported by WERNER as [Co₂{OH}₂(CH₃CO₂)H₂O(NH₃)₆]Br₃ actually has the formula [Co₂{CH₃CO₂(OH)₂}(NH₃)₆]Br₃ · CH₃COOH.     

The structure and mechanism of formation of C5H9O+ from ionized phytyl methyl ether

The recent proposal that ionized phytyl methyl ether [C₁₆H₃₃(CH₃)C=CHCH₂OCH ₃ ^+· ] undergoes an allylic rearrangement to ionized isophytyl methyl ether [CH₂=CHC(C₁₆H₃₃)(CH₃)OCH ₃ ^+· ] before elimination of an alkyl radical is discussed. Both literature precedent and new results in which the structure of the [M-C₁₆H ₃₃ ^· ]⁺ fragment ion is established by comparison of its collision-induced dissociation mass spectrum with the spectra of isomeric C₅H₉O⁺ ions of known structure are inconsistent with this proposal. The forma Hon of CH₃CH=CHCH=O⁺CH₃ by loss of a γ-alkyl substituent without skeletal isomerization rather than CH₂=CHC(CH₃)=O⁺CH₃ after allylic rearrangement is explained in terms of a mechanism that involves two 1,2-H shifts, followed by σ-cleavage of the resultant ionized enol ether, C₁₆H₃₃(CH₃)CH-CH=CHOCH ₃ ^+· .     

Reaktivität von Koordinationsverbindungen,XXIII [1]. Bildung und Zerfall des Sauerstoffadduktes mit N,N′-Bis-(4-(5)-imidazolylmethyl)-äthylendiamin-kobalt (II)-Ionen

In aqueous solution N, N′-bis-(4-(5)-imidazolylmethyl)-ethylenediamine-cobalt (II) (CoIMEN²⁺) takes up molecular oxygen giving μ-dioxygen-μ-hydroxo-bis-[N, N′-bis-(4-(5)-imidazolylmethyl)-ethylenediamine]-dicobalt (II). (Co IMEN)₂ O₂ (OH)³⁺ is exceptionally stable against irreversible autoxydation to Co^III species. Its absorption spectrum is very similar to that of the known analogous complex (CoTRIEN)₂ O₂ (OH)³⁺. The kinetics of formation and dissociation of (CoIMEN)₂O₂(OH)³⁺ are studied by spectrophotometry and with an oxygen specific electrode. The rate of the forward reaction is described by v_f = [CoIMEN²⁺]² · [O₂] · (k₁ + k₂ · [OH^?]) with k₁ = 9 · 10⁴ M^?2 s^?1 and k₂ = 1 · 10¹²M^?3 S^?1, at 25° and I = 0,2. A mechanism including hydroxylated as well as nonhydroxylated intermediates is proposed. Dissociation is preceeded by protonation of the oxygen adduct. At pH 1–2 the rate of dissociation is independent of [H⁺] and follows first order kinetics: v_D = k₃ · [(CoIMEN)₂O₂(OH)³⁺] with k₃ = 2.15 · 10^?2 S^?1.     

Poly(hydrogen Fluorides) with the Tetramethylammonium Cation: Preparation,Stability Ranges,Crystal Structures, [HnFn+1]− Anion Homology,Hydrogen Bonding F-H…︁F [2]

The melting diagram of the system (CH₃)₄NF? HF was studied between 50 and 100 mole-% HF and from ?185°C to the respective liquidus temperatures (at most 162°C) by difference thermal analysis aided by temperature-dependent X-ray powder diffraction. The system was found to be quasi-binary with the HF-rich intermediary stable compounds (CH₃)₄NF · 2 HF (melting point 110°C), (CH₃)₄NF · 3 HF (20°C, decomposition), (CH₃)₄NF · 5 HF (?76°C, decomposition), and (CH₃)₄NF · 7 HF (?110°C, decomposition), most of which undergo solid-solid phase transitions. Crystal structures were determined of the low-temperature form of (CH₃)₄NF · 2 HF (stable below 83°C, orthorhombic, space group Pbca, Z = 8 formula units per unit cell), the high-temperature form of (CH₃)₄NF · 3 HF (stable above ?87°C, monoclinic, P2/c, Z = 4), and of (CH₃)₄NF · 5 HF (tetragonal, I4 , Z = 2). The structures are those of poly(hydrogen fluorides) (CH₃)₄N[H_nF_n+1] with homologous anions [H₂F₃]^?, [H₃F₄]^?, and [H₅F₆]^?, respectively, formed by strong hydrogen bonding F? H…?F. The anion [H₅F₆]^? is the first one of this composition established by crystal structure analysis. Its structure can be written as [(FH)₂FHF(HF)₂]^? with four equivalent terminal hydrogen bonds of 248.4 pm and a very short central one of 226.6 pm (F…?F distances) through a 4 point of the space group.     

A comparative study on the behaviour of 1,3-diheterocyclopentanes (X = O,O; S,S; O,S) under electron impact. The formation of thioacetyl and thiiranyl cations

The electron-impact-induced mass spectra of 1,3-dioxolane (la), 1,3-dithiolane (2a) and 1,3-oxatbiolane (3a) and their 2-methyl (1b–3b) and 2,2-dimethyl [(CH₃)₂: 1c–3c or (CD₃)₂: 1d–3d] derivatives have been studied in detail to gain further insight into their ion structures and competing reaction pathways with low-resolution, high-resolution, metastable and collision-induced dissociation (CID) techniques. For compounds 1a–1d the most significant reaction is loss of H^˙ and CH₃^˙ by α-cleavage and a subsequent formation of CHO⁺ and C₂H₃O⁺ ions. The [M ? H]⁺ ions from 1a and 1b give a C₂H₃O⁺ ion which does not have the acyl cation structure as shown by their CID spectra. In compounds 3a–3d the sulphur-containing ions predominate, the C₂H₃O⁺ now having the acyl cation structure. 1,3-Dithiolanes (2a–2d) exhibit the most complicated fragmentation patterns. Furthermore the [M ? H]⁺ ion from 2a and [M ? CH₃]⁺ ion from 2b have different structures as well as the [M ? H]⁺ ion from 2b and [M ? CH₃]⁺ ion from 2c, as shown by their CID spectra. This can be utilized to explain why 3a–3c and 2a give principally a thiiranyl cation, whereas 2b gives a mixture of this and the thioacyl cation and 2c practically only the open-chain thioacetyl cation.     

Synthesis,Spectroscopy and Crystal Structures of Chiral Organic Ammonium Tetrathiometalates Showing N‐H···S and C‐H···S Interactions

The reaction of ammonium tetrathiometalate (NH₄)₂[MS₄] (M = W or Mo) with the R(+) or S(?) forms of the organic amine α‐methylbenzylamine [PhCH(CH₃)NH₂] results in the formation of the corresponding non‐centrosymmetric bis(α‐methylbenzylammonium) tetrathiometalate complexes [PhCH(CH₃)NH₃]₂[MS₄] (R‐ammonium M = W 1 ; R‐ammonium M = Mo 2 ; S‐ammonium M = W 3 , S‐ammonium M = Mo 4 ) which were characterized by elemental analysis, IR, Raman, UV‐Vis and CD spectra, X‐ray powder diffractometry and single crystal X‐ray crystallography. Compounds 1 ‐ 4 crystallize in the chiral space group P2₁ and constitute the first examples of structurally characterized chiral organic ammonium group VI tetrathiometalates. The structures of 1 ‐ 4 consist of two crystallographically independent chiral organic ammonium cations and a tetrahedral tetrathiometalate dianion. The N‐H···S and C‐H···S interactions between the anions and cations organise them such that the organic ammonium ions always point towards the S atoms of [MS₄]^2?.     

Electrospray Mass Spectrometry Study on Polynuclear Pd(II) and Ni (II) Complexes of 3, 6, 9, 16, 19, 22‐Hexaazatricyclo [22. 2.2.211,14] triaconta‐11, 13, 24, 26 (1), 27, 29‐Hexaene

Polynuclear Pd(II) and Ni(II) complexes of macrocyclic polyamine 3,6,9,16,19,22‐hexaazatricyclo[22.2.2.2^11,14]‐triaconta 11,13,24,26(l),27,29‐hexaene (L) in solution were investigated by electrospray ionization mass spectrometry (ESIMS). For methanol solution of complexes M₂LX₄ (M = Pd(II) and Ni(II), X= Cl and I), two main clusters of peaks were observed which can be assigned to [M₂LX₃]⁺ and [M₂LX₂]²⁺. When Pd₂LCl₄ was treated with 2 or 4 mol of AgNO₃, it gave rise formation of Pd₂LCl₂ (NO₃)₂ · H₂O and [Pd₂L(H₂O)_m(NO₃)_n]^(4‐n)+, respectively. ESMS spectra show that the dissociation of the former in the ionization process gave peaks of [Pd₂LCl₂]²⁺ and [(Pd₂LCl₂)NO₃]⁺, while dissociation of the later gave the peaks of [Pd₂L(CH₃CO₂)₂]²⁺ and [Pd₂L(CH₃CO₂)₂](NO₃) ⁺ in the presence of acetic acid. Similar species were observed for Pd₂LI₄ when treated with 4 mol of AgNO₃. When [Pd₂L · (H₂O)_m(NO₃)_n]^(4‐n)+ reacted with 2 mol of oxalate anions at 40°C, [Pd₄L₂(C₂O₄)₂(NO₃)₂]²⁺ and [Pd₄L₂(C₂O₄)₂ (NO₃)]³⁺ were detected. This implies the formation of square‐planar molecular box Pd₄L₂(C₂O₄)₂(NO₃)₄ in which C₂O₄^? may act as bridging ligands as confirmed by crystal structure analysis. The dissociation form and the stability of complex cations in gaseous state are also discussed. This work provides an excellent example of the usefulness of ESIMS in the identification of metal complexes in solution.     

Synthesen und Schwingungsspektren der homoleptischen Acetonitrilkomplex-Kationen [Au(NCCH3)2]+, [Pd(NCCH3)4]2+, [Pt(NCCH3)4]2+ und des Adduktes CH3CN · SbF5. Kristallstrukturen der Salze [M(NCCH3)4][SbF6]2 · CH3CN,M = Pd,Pt

The Syntheses and Vibrational Spectra of the Homoleptic Metal Acetonitrile Cations [Au(NCCH₃)₂]⁺, [Pd(NCCH₃)₄]²⁺, [Pt(NCCH₃)₄]²⁺, and the Adduct CH₃CN · SbF₅. The Crystal and Molecular Structures of [M(NCCH₃)₄][SbF₆]₂ · CH₃CN, M = Pd or Pt Solvolyses of the homoleptic metal carbonyl salts [M(CO)₄][Sb₂F₁₁]₂, M = Pd or Pt, in acetonitrile leads at 50 °C both to complete ligand exchange for the cations as well as to a conversion of the di-octahedral anion [Sb₂F₁₁]^– into [SbF₆]^– and the molecular adduct CH₃CN · SbF₅ according to: [M(CO)₄][Sb₂F₁₁]₂ + 7 CH₃CN → [M(NCCH₃)₄][SbF₆]₂ · CH₃CN + 2 CH₃CN · SbF₅ + 4 CO M = Pd, Pt The monosolvated [M(NCCH₃)₄][SbF₆]₂ · CH₃CN are obtained as single crystals from solution and are structurally characterized by single crystal x-ray diffraction. Both salts are isostructural. The cations are square planar but the N–C–C-sceletial groups of the ligands depart slightly from linearity. The new acetonitrile complexes as well as [Au(NCCH₃)₂][SbF₆] and the adduct CH₃CN · SbF₅ are completely characterized by vibrational spectroscopy.     

Kinetics and Mechanism of the Cerium(IV) Oxidation of Arnold's Base and the Protonation and Hydroxylation of Michler's Hydrol Blue

In aqueous H₂SO₄, Ce(IV) ion oxidizes rapidly Arnold's base((p-Me₂NC₆H₄)₂CH₂, Ar₂CH₂) to the protonated species of Michler's hydrol((p-Me₂NC₆H₄)₂CHOH, Ar₂CHOH) and Michler's hydrol blue((p-Me₂NC₆H₄)₂CH⁺, Ar₂CH⁺). With Ar₂CH₂ in excess, the rate law of the Ce(IV)-Ar₂CH₂ reaction in 0.100 M H₂SO₄ is expressed -d[Ce(IV)]/dt = k_app[Ar₂CH₂]₀[Ce(IV)] with k_app = 199 ± 8M^?1s^?1 at25°C. When the consumption of Ce(IV) ion is nearly complete, the characteristic blue color of Ar₂CH⁺ ion starts to appear; later it fades relatively slowly. The electron transfer of this reaction takes place on the nitrogen atom rather than on the methylene carbon atom. The dissociation of the binuclear complex [Ce(III)ArCHAr-Ce(III)] is responsible for the appearance of the Ar₂CH⁺ dye whereas the protonation reaction causes the dye to fade. In highly acidic solution, the rate law of the protonation reaction of Michler's hydrol blue is -d[Ar₂CH⁺]/dt = k_obs[Ar₂CH⁺] where K_obs = ((ac + 1)[H*] + bc[H⁺]²)/(a + b[H⁺]) (in HClO₄) and k_obs= ((ac + 1 + e[HSO₄^?])[H⁺] + bc[H⁺]² + d[HSO₄^?] + q[HSO₄^?]²/[H⁺])/(a + b[H⁺] + f[HSO₄^?] + g[HSO₄^?]/[H⁺]) (in H₂SO₄), and at 25°C and μ = 0.1 M, a = 0.0870 M s, b = 0.655 s, c = 0.202 M^?1s^?1, d = 0.110, e = 0.0070 M^?1, f = 0.156 s, g = 0.156 s, and q = 0.124. In highly basic solution, the rate law of the hydroxylation reaction of Michler's hydrol blue is -d[Ar₂CH⁺]/dt = k_OH[OH^?]₀[Ar₂CH⁺] with k_OH = 174 ± 1 M^?1s^?1 at 25°C and μ = 0.1 M. The protonation reaction of Michler's hydrol blue takes place predominantly via hydrolysis whereas its hydroxylation occurs predominantly via the path of direct OH attack.     

Synthesis,Structure and Magnetism of Bis[1,2,4‐tris(trimethylsilyl)cyclopentadienyl]europium

Bis[tris(trimethylsilyl)cyclopentadienyl]europium, Eu{C₅H₂[Si(CH₃)₃]₃}₂ (1) , has been synthesized by a modified transmetallation route between Tl{C₅H₂[Si(CH₃)₃]₃} and europium powder in toluene. 1 crystallizes in the monoclinic space group C2/c (No. 15) with a = 20.293(5) Å, b = 20.221(5) Å, c = 9.654(2) Å, β = 106.412(5)°, V = 3800.1(15) ų, Z = 4. The unit cell contains monomeric molecules that adopt a bent metallocene conformation with two partially staggered Cp? ligands. Magnetic susceptibility measurements in the temperature range 2–300 K display ideal Curie paramagnetic behaviour of the 4f⁷ system with Curie constant C = 9.6 × 10^?5 m³ K mol^?1 corresponding to temperature independent μ_eff = 7.8.     

Die Reaktion von Trichlornitromethan mit Eisencarbonylen Kristallstruktur von (PPh4)2[Fe2OCl6] · 2 CH2Cl2

Reaction of Trichloronitro Methane with Iron Carbonyls. Crystal Structure of (PPh₄)₂[Fe₂OCl₆] · 2 CH₂Cl₂ Trichloronitro methane reacts with Fe₂(CO)₉ or Fe₃(CO)₁₂ forming NO[FeOCl₂] which is composed of Nitrosyl ions and polymeric [FeOCl₂]^?. The reaction of NO[FeOCl₂] with POCl₃ affords Fe(O₂PCl₂)₃; with tetraphenyl phosphoniumchloride it forms the complex (PPh₄)₂[Fe₂OCl₆] which is soluble in CH₂Cl₂. The oxochloro ferrates are characterized by the aid of ⁵⁷Fe-Mössbauer spectra and by i.r. spectra. A single crystal of (PPh₄)₂[Fe₂OCl₆] · 2 CH₂Cl₂ was used to carry out a structural investigation by means of X-ray diffraction data (space group P1 , Z = 1, a = 1157.2(2), b = 1363.8(3), c = 1140.3(2) pm, α = 109.22(1)°, β = 95.23(1)°, γ = 67.24(2)°, R = 0.052 for 3814 reflexions with F₀ > 3σ). The [Cl₃Fe? O? FeCl₃]^2?-anion is found to have a centre of symmetry and thus, in accordance with the i.r. spectra, contains a linear bridge. High thermal parameters of the bridging oxygen atom and the chlorine ligands, however, allow interpretations as orientation disorder of slightly bent anions.     

[Mo2(O2C–CH3)4 · 1/2 {(CH2)6N4} · 1/2 CH2Cl2] – ein Donor‐Akzeptor‐Komplex mit supramolekularer Struktur

[Mo₂(O₂C–CH₃)₄ · ¹/₂ {(CH₂)₆N₄} · ¹/₂ CH₂Cl₂] – a Donor‐Acceptor Complex with Supramolecular Structure Yellow single crystals of [Mo₂(O₂C–CH₃)₄ · ¹/₂ {(CH₂)₆N₄} · ¹/₂ CH₂Cl₂] ( 1 ) have been obtained by the reaction of the silylated phosphaneimine Me₃SiNPEt₃ with [Mo₂(O₂C–CH₃)₄] in dichloromethane solution. 1 forms a three‐dimensional network with linear N–Mo:Mo–N and tetrahedral (CH₂)₆N₄Mo₄ moieties, which is topologically related with the PtS type. Space group P4₂/nnm, Z = 4, lattice dimensions at –70 °C: a = b = 1121.7(1), c = 1395.0(3) pm, R₁ = 0.0413.     

Über Metall-Stickoxid-Komplexe. XXV. Zur Kenntnis von Nitrosylcyano-Komplexen der Metalle der Eisengruppe

The binuclear nitrosylhalides of iron and cobalt react with cyanide to anionic complexes [M(NO)₂(CN)₂]^? (M = Fe, Co). Substituted monomeric compounds M(NO)₂LBr and Ni(NO)L₂Br lead primarily under replacement of bromide to nonionic complexes M(NO)₂LCN and Ni(NO)L₂CN. In general these complexes react with more cyanide yielding anions [M(NO)₂(CN)₂]^?, [Ni(NO)L(CN)₂]^? and [Ni(NO)(CN)₃]^2?. The paramagnetic dinitrosyliron compounds can be reduced to diamagnetic complexes by Na/Hg. A disproportion reaction of Co(NO)₂P(C₆H₅)₃CN forms a salt [Co(NO)₂ · (P(C₆H₅)₃)₂][Co(NO)₂(CN)₂], a similar salt can be made by the reaction of Na[Co(NO)₂(CN)₂] with [Co(NO)₂(NHP(C₆H₅)₃₂]Br. The IR spectra are discussed.     

Beiträge zur Chemie der Alkylverbindungen von Übergangsmetallen. XL. Über Lithium-alkenylmanganate(II)

Contributions to the Chemistry of Transition Metal Alkyl Compounds. XL. About Lithium Alkenylmanganates(II) MnCl₂ reacts with vinyl, 2,2-dimethylvinyl, allyl, and methallyl lithium giving rise to alkenyl manganates(II). In a pure state the compounds Li₂[Mn(CH?CH₂)₄] · 1.5 diox, Li₂[Mn(CH?C(CH₃)₂)₄] · 1.5 diox, Li₂[Mn(CH₂? CH?CH₂)₄] · 2.5 diox and Li₃[Mn(CH₂? C(CH₃)?CH₂)₅] · 2 diox were isolated. The compounds were characterized by elementary analysis, EPR and IR spectra, magnetic moments, and reactions with iodine.     

Reactions of the trimethylsilyl ion with 1,2-cyclopentanediol isomers in the collision region of a triple quadrupole instrument

Ion-molecule reactions with the trimethylsilyl ion were used to distinguish between cis- and trans-1,2-cyclopentanediol isomers. The ion kinetic energy of [Si(CH₃)₃]⁺ was varied from 0 eV to 15 eV (center of mass frame of reference). At low ion kinetic energies (<4 eV), there are significant differences in the relative stabilities and decomposition behavior of the adduct ions [M + Si(CH₃)₃]⁺. The cis-1,2-cyclopentanediol isomer favors decomposition of [M + Si(CH₃)₃]⁺ to yield the hydrated trimethylsilyl ion [Si(CH₃)₃OH₂]⁺ at m/z 91. For the trans isomer, the formation of the hydrated trimethylsilyl ion is an endothermic process with a definite threshold ion kinetic energy.