Reactivity and gelation. II. Substitution effect

The development in Paper I is extended to multifunctional condensations where the functional groups exhibit unequal reactivities induced by substitution effects in the course of the polymerization. A system R(A)₂/R′(B)₃ is examined to determine how the gel point varies with the strength and positive or negative sense of the substitution effect. As in Paper I, intramolecular interactions are not considered.     

Reactivity of germylmercurate complexes

The selective insertion of sulfur into the GeHg bond in the ionic complex {[(C₆F₅)₃Ge]3Hg}⁻Cp₂Co⁺ results in the formation of mono-, di- and trithiolate derivatives. The compounds have been characterized by elementary analysis, IR, ¹⁹F and ¹⁹⁹Hg NMR spectroscopy. The molecular structure of {Hg[SGe(C₆F₅)₃]₃}⁻-Cp₂Co⁺ has been determined by X-ray analysis. Sulfur-containing complexes are donors of chalcogen atoms in the reaction with covalent and ionic polynuclear organometallic compounds. Ytterbium dicyclopentadienide and vanadocene displace cobaltocene from {[(C₆F₅)₃Ge]₃Hg}⁻-Cp₂Co⁺, and Cp₂Co removes thallium from its germylmercurate complex. A general scheme for the reaction of vanadocene with cobalticinium germylmercurate has been proposed. The zerovalent triphenylphosphine complex of platinum Pt(PPh₃)₄ destroys the ionic structure of {[(C₆F₅)₃Ge]₂HgI}⁻(C₆H₆)2Cr⁺to give dibenzenechromium iodide and a polynuclear compound with GeHgPtGe chain.     

Reactivity of dimetallated benzalazines

Summary The action of dpe or PPh₃ on dimetallated benzalazines in presence of NaClO₄ gives to ionic compounds only with dpe. can be obtained from [Pd(p-XC₆H₃CH=N-)Cl(PPh₃)₂]₂ and AgClO₄.     

ChemInform Abstract: Structure and Reactivity of Thiophosphoranyl Radicals. A Quantum Chemical Study.

By calculation of various optimized geometries for the (PH₃SH)- radical using the unrestricted Hartree-Fock method the (PH₃SH-e)- form resembling a trigonal-bipyramidal structure with missing equatorial substituent is shown to be the preferential structure.     

Reactivity of sodium triphosphate crystal hydrates

Kinetics of thermal decomposition of single crystals and polycrystalline samples of Na₅P₃O₁₀·6D₂O and Na₅P₃O₁₀·6H₂O, interaction of fine-crystalline Na₅P₃O₁₀·1.6H₂O with humid gaseous ammonia were studied using TLC, XRDA, IRS, TG, DTA, DSK.     

Reactivity of an Intramolecular Fluorophosphonium Fluoroborate

The reactions of the intramolecular frustrated Lewis pair‐adduct Ph₂PC(p‐Tol)?C(C₆F₅)B(C₆F₅)₂(CNtBu) with XeF₂ gave Ph₂P(F)C(p‐Tol)?C(C₆F₅)B(F)(C₆F₅)₂ ( 3 ). This species reacts with two equivalents of Al(C₆F₅)₃?C₇H₈ producing the salt, [Ph₂P(F)C(p‐Tol)?C(C₆F₅)B(C₆F₅)₂][F(Al(C₆F₅)₃)₂] ( 4 ), whereas reaction with HSiEt₃/B(C₆F₅)₃ gave Ph₂P(F)C(p‐Tol)?C(H)B(C₆F₅)₃ ( 5 ). The photolysis of 3 resulted in aromatization affording the phenanthralene derivative Ph₂P(F)C(p‐Tol(o‐C₆F₄))?CB(F)(C₆F₅)₂ ( 6 ).     

Reactivity of N-arylsulfonyl-1,4-benzoquinone imines. Reaction with hydrazoic acid

N-Arylsulfonyl-2-halo-1,4-benzoquinone imines react with hydrazoic acid in boiling acetic acid via two pathways: the 1,4-addition and nucleophilic replacement of the halogen atom by an azido group, followed by the 1,4-addition of HN₃. In the reaction of N-arylsulfonyl-2,6-dihalo-1,4-benzoquinone imines with hydrazoic acid, both halogen atoms are replaced by azido groups, while N-p-tolylsulfonyl-2-methyl-1,4-benzoquinone imine takes up HN₃ molecule according to the 1,4-addition pattern.     

Disilenyl Silylene Reactivity of a Cyclotrisilene

The highly reactive silicon congeners of cyclopropene, cyclotrisilenes (c‐Si₃R₄), typically undergo either π‐addition to the Si=Si double bond or σ‐insertion into the Si?Si single bond. In contrast, treatment of c‐Si₃Tip₄ (Tip=2,4,6‐ⁱPr₃C₆H₂) with styrene and benzil results in ring opening of the three‐membered ring to formally yield the [1+2]‐ and [1+4] cycloaddition product of the isomeric disilenyl silylene to the C=C bond and the 1,2‐diketone π system, respectively. At elevated temperature, styrene is released from the [1+2]‐addition product leading to the thermodynamically favored housane species after [2+2] cycloaddition of styrene and c‐Si₃Tip₄.     

Probing the Reactivity of the Potent AgF2 Oxidizer. Part 2: Inorganic Compounds

The reactivity of Ag^IIF₂ towards forty two inorganic compounds containing oxo‐ and chloro‐ ligands, has been investigated. Five families of compounds were studied: (i) binary oxides of metals and nonmetals, (ii) ternary salts of inorganic oxo acids, (iii) concentrated or anhydrous oxo‐ acids, (iv) binary and ternary chlorides and (v) oxochlorides. At low temperatures up to 200 °C AgF₂ readily oxidizes HgO, B₂O₃, PbO₂, As₂O₅, Ag₂SO₄, LiBO₂, K₂CO₃, KVO₃, Ag₂WO₄, and AgMnO₄ with concomitant oxygen evolution. In the same conditions V₂O₅, CrO₃, MoO₃, WO₃, CuO, Tl₂O₃, I₂O₅, Re₂O₇, K₂SO₄, HgSO₄, KSO₃F, KNO₃, KClO₄, KIO₄, BaCrO₄, KMnO₄ and KReO₄ resist the action of AgF₂ but many of these compounds get oxidized at higher temperatures (up to nearly 300 °C). Substantial inertness of sulfates, chromates, nitrates, perchlorates, permanganates and perrhenates suggests that one might attempt to synthesize salts of divalent silver with these anions. AgF₂ vigorously reacts with H₂SO₄ (fuming, 30% SO₃), HSO₃Cl (100%), HClO₄ (70%), and HNO₃ (fuming, 100%) at room temperature yielding salts of Ag^I and O₂; for HClO₄ and HNO₃ pre‐cooled to ?35 °C metastable perchlorate / nitrate complexes of Ag^II are obtained. Anhydrous HSO₃F behaves similar to HSO₃CF₃ (see Part 1 of this series) yielding slow methathetical conversion of AgF₂ without concomitant redox reaction. Majority of chlorides and oxochlorides studied (AgCl, AuCl₃, KAuCl₄, WCl₆, WOCl₄, MoOCl₄, MoO₂Cl₂) react with AgF₂ at temperatures below 160 °C. Reaction with SiCl₄ (in contrast to CCl₄) is violent and very exothermic at room temperature. Liquid CrO₂Cl₂ (at room temperature) and solid WO₂Cl₂ (up to 180 °C) are kinetically inert to AgF₂. We do not observe intercalation of AgF₂ with various redox—inert oxo‐ and chloro‐ Lewis bases at the experimental conditions.     

Reactivity of thiophosphinous acid bound to ruthenium

The thiophosphinous acid coordinated to ruthenium through the phosphorus atom in [CpRu(PPh₃)₂(PH₂SH)]CF₃SO₃ (1) is deprotonated in the presence of proton sponge to yield the neutral compound [CpRu(PPh₃)₂(PH₂S)] (2), where the thiophosphinite, PH₂S⁻, anion remains bound to the metal through the phosphorus atom. The parent complex 1 is easily restored in the presence of a weak acid. The sulfur of the coordinated anion may be alkylated with CF₃SO₃Me to yield [CpRu(PPh₃)₂(PH₂SCH₃)]CF₃SO₃ (3), the methyl thioester of the acid being bound to ruthenium through the phosphorus. The new compounds have been characterized by elemental analyses, IR and multinuclear NMR spectroscopy. The crystal structure of 2 · CH₃CN has been determined by X-ray diffraction methods.     

Reactivity and gelation. I. Intrinsic reactivity

The method of Case is used with the Flory-Stockmayer gelation criterion to derive a critical transition equation for polycondensation of multifunctional reactants bearing coreactive functional groups of two species A and B, where the B groups may be of unequal intrinsic reactivity. Systems of the types R(A)₂/R′(B)₄ and R(A)₂/R′(B)₄/R′′(B)₂ are considered with the B groups divided into two classes characterized by a reactivity ratio in the range 0.1 to 10. If the reactivities are sufficiently different the polymerization can be regarded as a multistage process. Intramolecular reactions are not considered.     

Synthesis and Reactivity of New Functionalized Perfluoroalkylfluorophosphates

A new efficient synthesis of functionalized perfluoroalkyl fluorophosphates by oxidative addition of Me₂NCH₂F to the electron‐deficient phosphanes (C₂F₅)_nPF_3?n (n=0–3) is reported. The initially formed zwitterionic, hexacoordinated phosphates [(C₂F₅)_nF_5?nP(CH₂NMe₂?CH₂NMe₂)] are converted into the corresponding phosphonium salts [(Me₃PCH₂NMe₂]⁺[(C₂F₅)_nF_5?nP(CH₂NMe₂)]^? by treatment with PMe₃. In addition [(C₂F₅)₃F₂P(CH₂NMe₂?CH₂NMe₂)] can undergo a 1,3‐methyl shift from the internal to the terminal nitrogen—a structural characterization was achieved from the CF₃ analogue. Reaction of [(C₂F₅)₃F₂P(CH₂NMe?CH₂NMe₃)] and PMe₃ gave rise to the formation of the zwitterionic phosphonium phosphate [(C₂F₅)₃F₂P(CH₂NMe?CH₂PMe₃)], which was fully characterized by X‐ray diffraction analysis. Moreover, an efficient one‐pot synthesis of Cs⁺[(C₂F₅)₃F₂P(CH₂NMe₂)]^? was pursued. This salt turned out to be a useful nucleophile in several alkylation reactions.     

Reactivity of di-n-butyl-dicyclopentadienylzirconium towards amido stabilized stannylenes

Reaction of Sn[(N(C₆H₃iPr₂-2,6)(SiMe₃)]₂ and [{Sn(N(C₆H₃iPr₂-2,6)(SiMe₃)(μ-Cl)₂] with di-n-butyl-dicyclopentadienylzirconium yielded the trimetallic a carbene-like complex {[(N(C₆H₃iPr₂-2,6)(SiMe₃)](n-Bu)Sn}₂Cp₂Zr. The oxidation of {[(N(C₆H₃iPr₂-2,6)(SiMe₃)](n-Bu)Sn}₂Cp₂Zr by oxygen gives the five-membered dioxadistannazirconacyclic complex {[(N(C₆H₃iPr₂-2,6)(SiMe₃)](n-Bu)Sn}₂O₂Cp₂Zr.     

The Reactivity of Hexafluorothioacetone and Hexafluoroacetone versus Phosphites

Abstract

The dimer of hexafluorothioacetone reacted with various phosphites to form thiophosphates and bis(trifluoromethyl)methylenphosphoranes, being unstable in the case of (Me₃SiO) P(OMe)_3-n, (n=1?3), where phosphonates (Me₃SiO)_n-1(MeO)_3-nP(O)[C(CF₃)=CF₂] (n=1-3) and Me₃SiF were observed. In general, cyclic phosphites behaved similar to acyclic ones. The resulting bis(trifluoromethyl)methylenphosphoranes were thermally stable except compound A, because of a new intramolecular fluorine transfer to phosphorus forming fluorophosphorane B.     

Reactivity of digallane toward nitrogen-containing compounds

The reactions of [LGa–GaL] (L = dpp-bian = 1,2-bis[(2,6-di-isopropylphenyl)imino]acenaphthene) with ammonia and pyrrolidine in toluene lead to the formation of adducts [L(NH₃)Ga–Ga(NH₃)L], [L(HNC₄H₈)Ga–GaL] and [L(HNC₄H₈)Ga–Ga(HNC₄H₈)L], respectively. In contrast, the reaction between crystalline digallane and an excess of pyrrolidine leads to the formation of compound [LGa(NC₄H₈)(HNC₄H₈)]. The complex [LGa(C₅H₅N)(μ-O)Ga(C₅H₅N)L] was obtain from reaction of digallane with N₂O in the presence of pyridine.     

Reactivity of metal-metal bonds: II. Exchange reactions of trimethyltin derivatives of manganese and iron

The reactivity of Me₃SnMn(CO)₅, (CH₂CHCH₂)₃SnMn(CO)₅, Me₃SnFeCp(CO)₂, and Me₂Sn[FeCp(CO)₂]₂ has been investigated with respect to iodine, organomercury chlorides, trialkyl- and triarylchlorosilane, inorganic chlorides (SiCl₄, SnCl₄, TiCl₄, ZnCl₂, HgCl₂) and Mn₂(CO)_l0.Iodination proceeded with dominant metal-metal bond cleavage in all solvents used, as was the case in most of the subsequent reactions, with the exception of the triallyltin derivative where carbon—metal bond fission occurred.Me₃SnFeCp(CO)₂ reacted with MeHgCl in a $\text{1}\text{1}$ ratio in DMSO-d₆ to give initially MeHgFeCp(CO)₂ and Me₃SnCl which subsequently gave Me₄Sn, Me₂Hg, Hg[FeCp(CO)₂]₂ and ClHgFeCp(CO)₂. In contrast with the phenyl analogue, the intermediate MeHgFeCp(CO)₂ was not stable enough to be isolated. Me₂Sn[FeCp(CO)₂]₂ reacted similarly but secondary reactions yielded Me₃SnCl and, using excess MeHgCl, Me₂SnCl₂. Reaction of Me₃SnMn(CO)₅ followed similar patterns but in this instance MeHgMn(CO)₅ appeared much more stable than PhHgMn(CO)₅.Pathways accounting for all the products are discussed. Evidence is also presented for a range of exchange reactions with a variety of inorganic and organometallic chlorides.     

Reactivity of polychlorophenylmercury compounds with 1,10-phenanthroline

The action of 1,10-phenanthroline (phen) on the THF solutions of RHgCl (R = 2,5-C₆H₃Cl₂; 2,3,4? and 2,4,6-C₆H₂Cl₃; 2,3,4,5?, 2,3,4,6?, and 2,3,5,6-C₄HCl₄ and C₆Cl₅) gives RHgCl (phen) when R contains two chlorine substituents in ortho (R = 2,4,6-C₆H₂Cl₃; 2,3,4,6?, and 2,3,5,6-C₆HCl₄ and C₆Cl₅), but the symmetrisation reaction occurs when R = 2,5-C₆H₃Cl₂; 2,3,4-C₆H₂Cl₃ and 2,3,4,5-C₆HCl₄. The action of phen on HgR₂ only gives HgR₂ (phen) when R = 2,3,4,5-C₆HCl₄. Compounds of the type RHgMe do not react with phen. These results indicate that steric citects are as important as the electronegativity of R in the formation of tetracoordinated mercury compounds.     

Synthesis,Reactivity and Structural Properties of Trifluoromethylphosphoranides

Phosphoranides are interesting hypervalent species which serve as model compounds for intermediates or transition states in nucleophilic substitution reactions at trivalent phosphorus substrates. Herein, the syntheses and properties of stable trifluoromethylphosphoranide salts are reported. [K(18-crown-6)][P(CF₃)₄], [K(18-crown-6)][P(CF₃)₃F], and [NMe₄][P(CF₃)₂F₂] were obtained by treatment of trivalent precursors with sources of CF₃⁻ or F⁻ units. These [P(CF₃)_4-nF_n]⁻ (n=0–2) salts exhibit fluorinating (n=1–2) or trifluoromethylating (n=0) properties, which is disclosed by studying their reactivity towards selected electrophiles. The solid-state structures of [K(18-crown-6)][P(CF₃)₄] and [K(18-crown-6)][P(CF₃)₃F] are ascertained by single crystal X-ray crystallography. The dynamics of these compounds are investigated by variable temperature NMR spectroscopy.     

Different Reactivity of As4 towards Disilenes and Silylenes

The activation of yellow arsenic is possible with the silylene [PhC(NtBu)₂SiN(SiMe₃)₂] ( 1 ) and the disilene [(Me₃Si)₂N(η¹-Me₅C₅)Si=Si(η¹-Me₅C₅)N(SiMe₃)₂] ( 3 ). The reaction of As₄ with 1 leads to the unprecedented As₁₀ cage compound [(LSiN(SiMe₃)₂)₃As₁₀] ( 2 ; L=PhC(NtBu)₂) with an As₇ nortricyclane core stabilized by arsasilene moieties containing silicon(II)bis(trimethylsilyl)amide substituents. In contrast, the compound [Cp*{(SiMe₃)₂N}SiAs]₂ ( 4 ) containing a butterfly-like diarsadisilabicyclo[1.1.0]butane unit is formed by the reaction of As₄ with the disilene 3 . Both compounds were characterized by single-crystal X-ray diffraction analysis, NMR spectroscopy, and mass spectrometry. The reaction outcomes demonstrate the different reaction behavior of yellow arsenic (As₄) compared to white phosphorus (P₄) in the reactions with the corresponding silylenes and disilenes.     

Reactivity of ytterbium in liquid ammonia

A solution of metallic ytterbium in liquid ammonia reacts readily with various carbonyl complexes of metals to form the corresponding lanthanide carbonylmetallates. The reaction of an excess of Yb in liquid NH₃ with [CpFe(CO)₂]₂ gave (THF)₄Yb[Fe(CO)₂Cp]₂ in 42% yield. It was suggested that the resulting complex contains two equivalent Yb−Fe bonds. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1883–1885, October, 1997.