Reaction of grayanotoxin-II with thallium (III) nitrate

Reaction of grayanotoxin-II (1) with thallium nitrate gave 3(S), 20-epoxy-6 (S), 14 (R), 16 (R)-trihydroxy-5-oxo-5, 10-seco-ent-kaur-1 (10) -ene (2). The structure of 2 was elucidated by the X-ray diffraction analysis of its reduction product (3).     

Oxidation of 4-chromanones with thallium(III) nitrate

Treatment of 4-chromanones 1a-g with thallium(III) nitrate in acidic methanol results mainly in dehydrogenation, whereas α-methoxylation and/or Taylor-McKillop rearrangement predominate in trimethyl orthoformate. The mechanistic features of these oxidations are briefly discussed.     

The reaction of sulfur with organic compounds

The most effective catalyst for thionation of cumenes to 4-aryl-1, 2-dithiol-3-thiones, have been proven to be sym-diphenylguanidine, mercury acetamide, mercaptobenzthiazole + ZnO. The way in which thionation of cumeme derivatives depends on the nature of the substituent in the aromatic ring is investigated. Eight derivatives (4 previously unknown) of 4-phenyl-1, 2-dithiol-3-thione, with a chlorine atom and an alkyl or alkoxy group in the benzene ring are synthesized and described.For previous papers see [1–6].     

(Chloromethyl)thallium(III) compounds

Aryl(chloromethyl)thallium chlorides, Ar(ClCH₂)TlCl (Ar=C₆H₅, p-CH₃C₆H₄) have been prepared by treatment of arylthallium dichlorides with diazomethane. The derived carboxylates, Ar(ClCH₂)TlX, react with HgX₂ to give the dicarboxylates, (ClCH₂)TlX₂ (X = OCOCH₃, OCOC₃H₇-i) and with tetramethyltin to give CH₃(ClCH₂)TlX compounds. R(ClCH₂)TIX compounds (R = CH₃, C₆H₅, p-CH₃C₆H₄) undergo disproportionation in methanol to R₂TlX and (ClCH₂)₂TlX compounds.     

Oxidation of trans-alloocimene by thallium(III) nitrate

We have obtained 2,7-dimethoxy-2,7-dimethyl-3,5-octadiene by the action of thallium(III) nitrate on trans-allo-ocimene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1087–1089, May, 1990.     

Investigation of the reaction: of sulfur with organic compounds

A new method for synthesizing 5-aryl-1, 2-dithiol-3-thiones is worked out. It is based on sulfuration of nuclear-substituted n-propylbenzenes in the presence of mercaptobenzothiazole.For Part VIII see [1].     

Chlorobis(polyfluorophenyl)thallium(III) complexes and their reactions with gold(I) and tin(II) compounds

The reaction of TlCl₃ with RLi leads to complexes of the general formula TlR₂Cl (R = C₆F₅, p-C₆F₄H, m-C₆F₄H, 2,4,6-C₆F₃H₂, p-C₆FH₄ or m-CF₃C₆H₄). Some of these undergo oxidative addition reactions with gold(I) complexes to give polyfluorophenyl derivatives of the types AuR₂ClL and Au(C₆F₅)R₂(tht) (tht = tetrahydrothiophen), and with SnCl₂ to give oily materials from which stable solids of the general formula Q[SnR₂Cl₃] can be isolated by addition of QCl (Q = Et₄N or Ph₃BzP).     

Study of the reaction of sulfur with organic compounds

A study is made of the action of sulfur on halogen derivatives of iso- and n-propylbenzene, with 1–3 chlorine or bromine atoms at various places in the side chain. Reaction of sulfur with α-chlorocumene, α, β-dichlorocumene, and α, β, β-trichlorocumene and mixtures of these, proves to be a new convenient method of preparing 4-phenyl-1,2-dithio-3-thione (40% yield). Sulfuration of mono-, di- and tri-exo-halogen derivatives of n-propylbenzene gives 5-phenyl-1,2-dithiol-3-thione in 11–18% yield. For Part XII see [1].     

Study of the reaction of sulfur with organic compounds

The reaction of sulfur with phenylchloromethanes of the type (C₆H₅)_mCCl_nH_{4-m -n}(m=1–3; n3) is investigated. New simple methods of synthesizing tetraphenylthiophene (from C₆H₅CH₂Cl) and thianaphtheno [3, 2-b] thianapthene or 2-phenyl-3-chlorothianaphthene (from C₆H₅CHCl₂) are developed. All the heterocyclic sulfur compounds synthesized are oxidized to the corresponding sulfones, Diphenylchloromethane when heated with sulfur smoothly gives a high yield of tetraphenylethylene, and triphenylchloromethane treated similarly gives triphenylmethane. C₆H₅CCl₃ and (C₆H₅)₂CCl₂ undergo practically no reaction with sulfur under the conditions investigated.For Part VII see [1].     

Novel reactions of 1,1,4,4-tetraaryl-1,2,3-butatrienes with elemental sulfur and selenium

Sulfurization and selenation reactions of 1,1,4,4-tetraaryl-1,2,3-butatrienes were examined to give novel 1,2,3,4,5-pentathiepane and 1,2,5-triselenepane ring systems. Further degradation of these new heterocycles using DBU/DMF was also described.     

A study of the reactions of sulfur with organic compounds

On the basis of the reaction of sulfur with exo-halogen derivatives of ethylbenzene and styrene, new and simple methods of synthesis have been developed for 2,4-diphenylthiophene (from C₆H₅CHBrCH₃), 2, 5-diphenylthiophene (from C₆H₅CCl=CH₂), 2,3-dichlorothionaphthene (from C₆H₅CCl2CHCl₂), and the previously unknown dithianaphtheno-[2,3-b;2,3-e]-1,4-dithiadiene (from C₆H₅CHClCHClBr). The latter compound is also formed by the action of sulfur on C₆H₅CCl₂CH₂Cl or C₆H₅CHClCHCl₂ in the presence of HBr. The derivatives of thianaphthene obtained have been oxidized to the corresponding sulfones.For communication XIV see [1].Presented on 11 May 1966 at the Second Symposium on Organic Compounds of Sulfur at Groningen (Holland).     

Reaction of organic sulfur compounds with superoxide anion—III : Oxidation of organic sulfur compounds to sulf1nic and sulfonic acids

Organic sulfur compounds such as disulfide, thiolsulfinate, thiolsulfonate, thiol, sodium thiolate, and sodium sultinale were readily oxidized to both sulfinic and sulfonic acids with superoxide anion generated from potassium superoxide and 18-crown-6-ether under mild conditions. However, both sulfide and sulfoxide did not react with superoxide anion, O₂^-. Although thiol was easily oxidized to disulfide with O₂^? at room temperature, it was oxidized further with O₂^? at 60° to the corresponding sulfinic and sulfonic acids. Symmetrical disulfide was obtained in the reaction of unsymmetrical thiolsulfinate or thiolsulfonate along with both sulfinic and sulfonic acids. Most reactive was thiolsulfinate which reacted at lower temperature ranging between ?40 and 0° to afford the products within 30 min. Relative reactivities fall in the following order: thiolsulfinate > thiolsulfonate > disulfide ? sodium thiolate ? sodium sulfinate. Polar solvents such as pyridine and acetonitrile were more effective than such a less polar solvent as benzene in the oxidation of the substrate, and increased amount of the crown ether shortened the reaction time. Nucleophilic attack of O₂^? and electron transfer processes are believed to be involved in these oxidations.     

A study of the reaction of sulfur with organic compounds

The reaction of sulfur with isomeric exo-polychloro derivatives of iso- and n-propylbenzenes containing from 4 to 6 chlorine atoms in the side chain at 200°–300° C has been studied. The reaction of sulfur with α, β, β, β′-tetrachloro- and α, β, β, β′, β′-pentachlorocumenes leads to the formation of the previously unknown thianaphtheno-[2, 3-d]-1, 2-dithiole-3-thione (yield 48%) and thionaphtheno[2,3-d]-3-chloro-1, 2-dithiolium chloride (yield 65%), respectively. The sulfuration reaction of the isomeric exo-tetrachloro-and exo-pentachloro-n-propylbenzenes leads to the formation of 4-chloro-5-phenyl-1, 2-dithiole-3-thione (yield 5–35%). The exo-hexachloro derivatives of iso- and n-bromobenzenes, on being heated with sulfur, form only resinous sulfuration products.     

A study of the reaction of sulfur with organic compounds

The reaction of sulfur with isomeric exo-polychloro derivatives of iso- and n-propylbenzenes containing from 4 to 6 chlorine atoms in the side chain at 200°–300° C has been studied. The reaction of sulfur with , , , -tetrachloro- and , , , , -pentachlorocumenes leads to the formation of the previously unknown thianaphtheno-[2, 3-d]-1, 2-dithiole-3-thione (yield 48%) and thionaphtheno[2,3-d]-3-chloro-1, 2-dithiolium chloride (yield 65%), respectively. The sulfuration reaction of the isomeric exo-tetrachloro-and exo-pentachloro-n-propylbenzenes leads to the formation of 4-chloro-5-phenyl-1, 2-dithiole-3-thione (yield 5–35%). The exo-hexachloro derivatives of iso- and n-bromobenzenes, on being heated with sulfur, form only resinous sulfuration products.For part XVI, see [1].     

A study of the reaction of sulfur with organic compounds

The reactions of sulfur with alip-halogen derivatives of 1,2-diphenylethane, 1,2-diphenylethylene, and tetraphenylethane have been studied. A new method for the production of tetraphenylthiophene (from C₆H₅CHClCHClC₆H₅), benzothieno[3,2-b]benzothiophene (from C₆H₅CHClCCl₂C₆H₅), and of 2-phenylbenzo[b] thiophene (from C₆H₅CHBrCHBrC₆H₅) has been developed. On being treated with sulfur, tetraphenyl-1,2-dichloroethane is converted into tetraphenylethylene. 1,2-Diphenylethylene reacts with sulfur in the presence of hydrogen bromide forming 2-phenylbenzo[b]thiophene and tetraphenylthiophene.For part XVII, see [1].     

Volume change of ion pair formation: Rubidium nitrate and thallium(I) nitrate in water

Density data for dilute aqueous solutions of RbNO ₃ and TlNO ₃ at 25°C lead to the following equations for the apparent molal volumes: RbNO₃: Φ_V = 43.0₇ + 2.46c ^1/2 + 0.15c (0?0.41M) TINO₃: Φ_V = 39.5₀ + 10.83c ^1/2 ? 25.46c + 26.0c ^3/2 (0.03?0.25M) From these expressions and a semiempirical equation for Φ_v of a completely dissociated 1:1 electrolyte, values of ΔΦ_v for ion pair formation at c=0.10 are calculated to be+5 ml-mole^?1 for RbNO ₃ and+12 ml-mole^?1 for TlNO ₃ . Comparison of ΔΦ_v with the electrostriction volume effect suggests that virtually all of the electrostriction is removed in the formation of the TlNO ₃ ion pair but only about half with RbNO ₃ . Values of ΔΦ_v are in poor agreement with those estimated from electrostatic theories of ion pair formation.     

Organothallium compounds : XVII. Halogenobis(polyfluorophenyl)thallium(III) complexes

The preparations, stabilities and structures of the complexes R₂TlX and R₂ LTlX (R = C₆F₅, p-HC₆F₄, or o-HC₆F₄; X = Br or Cl; L = Ph₃PO, 2,2′-bipyridyl (bpy) or Ph₃P) have been examined or (R = C₆ F₅) reinvestigated. The derivatives R₂TlX are monomeric in acetone, from which the complex (p-HC₆F₄)₂ Me₂COTIBr has been isolated. In this solvent, the complexes R₂LTlX (L = Ph₃PO, bpy, or Ph₃P) undergo partial dissociation by loss of L. When L = bpy, there is also slight ionization into R₂LTl⁺ and R₂TlX^?₂. The acceptor properties of R₂TlX compounds towards uncharged ligands decrease R = C₆F₅ ? p-HC₆F₄ > o-HC₆F₄ > Ph. Dimeric behaviour is observed for R₂TIX compounds in benzene, whilst R₂LTlX (L = Ph₃PO or bpy) derivatives show slight but significant association. In the solid state, R₂TlX compounds are considered to be polymeric with five coordinate thallium, and R₂LTlX derivatives to be dimeric with five (L = Ph₃PO) or six (L = bpy) coordinate thallium by contrast with four coordinate dimeric and four or five coordinate monomeric structures previously proposed for the respective pentafluorophenyl derivatives. Halogen bridging is unsymmetrical for R = C₆F₅ or p-HC₆F₄, but may be more symmetrical for R = o-HC₆F₄ when L = Ph₃PO or bpy. Reported structural data for the complexes (C₆F₅)LTlX (L = Ph₃AsO, Ph₃P, Ph₃As, or 1,10-phenanthroline; X = Br or Cl) and (C₆F₅)₂TlCl^?₂ are reinterpreted and the proposed structures revised.