Trimethyltin Fluoride Research Articles

Front Cover: Synthesis of Actinide Fluoride Complexes Using Trimethyltin Fluoride as a Mild and Selective Fluorinating Reagent (Eur. J. Inorg. Chem. 11/2018)

Front Cover: Synthesis of Actinide Fluoride Complexes Using Trimethyltin Fluoride as a Mild and Selective Fluorinating Reagent (Eur. J. Inorg. Chem. 11/2018)

Synthesis of Actinide Fluoride Complexes Using Trimethyltin Fluoride as a Mild and Selective Fluorinating Reagent

AbstractInvited for the cover of this issue are JaquelineàL. Kiplinger and co‐workers from Los Alamos National Laboratory, New Mexico, USA. The cover image shows the versatility of trimethyltin fluoride (Me3SnF) as a reagent for the conversion of actinide halides to actinide fluorides.

Synthesis of Actinide Fluoride Complexes Using Trimethyltin Fluoride as a Mild and Selective Fluorinating Reagent

Trimethyltin fluoride (Me3SnF) is a mild and selective reagent for the installation of actinide fluoride bonds as demonstrated by the room temperature synthesis of a variety of organometallic and inorganic thorium(IV), uranium(IV), and uranium(V) fluoride complexes {(1,2,4‐tBu3C5H2)2ThF2, (C5Me5)2U(F)(O‐2,6‐iPr2C6H3), U(F)(O‐2,6‐tBu2C6H3)3, U(F)[N(SiMe3)2]3, (C5Me5)2UF2(L) (L = O=PMe3, O=PPh3, O=PCy3), and (C5Me5)2U(F)(=N‐2,6‐iPr2C6H3)} from their corresponding chloride, bromide, and iodide analogues. From these reactions, the new (C5Me5)2UF2(L) (L = O=PPh3, O=PCy3) uranium fluoride complexes were isolated and characterized by NMR spectroscopy and X‐ray crystallography.

The structure of trimethyltin fluoride.

The solid-state structure of (CH3)3SnF was reinvestigated by X-ray diffraction techniques as well as by multi-nuclear solid-state NMR spectroscopy. Trimethyltin fluoride crystallizes from hot ethanol in the orthorhombic space group Pnma at room temperature and changes to a low-temperature orthorhombic phase (space group: Cmcm) below -70 °C. In both modifications, trimethyltin fluoride adopts a linear chain structure with symmetric fluorine bridges, in contrast to previous reports. During its synthesis, (CH3)3SnF precipitates in another, poorly crystalline modification, as shown by powder X-ray diffraction. Solid-state MAS NMR experiments of both room-temperature phases of (CH3)3SnF (non-recrystallized and recrystallized) were carried out for the (1)H, (13)C, (19)F, and (119)Sn nuclei. The (119)Sn{(19)F, (1)H} and (19)F{(1)H} NMR spectra offer unambiguous determination for the (19)F and (119)Sn shielding tensors. The (119)Sn{(1)H} solid-state NMR spectra are in agreement with pentacoordination of Sn in this compound for the non-recrystallized and the recrystallized modifications. Based on the solid-state NMR results, the non-recrystallized modification of (CH3)3SnF also consists of linear, symmetrically fluorine-bridged chains, and differs from the recrystallized orthorhombic phase only in packing of the chains.

Titanocene Difluorides with Improved Cytotoxic Activity

Titanocene difluorides can be obtained by halide metathesis of the respective titanocene dichlorides with trimethyltin fluoride (Me(3)SnF), giving access to a new class of cytotoxic active substances. Furthermore, an improved method for the synthesis of diaryl-substituted titanocene dichlorides is presented.

High Yield Access to Silylene RSiCl (R = PhC(NtBu)2) and Its Reactivity toward Alkyne: Synthesis of Stable Disilacyclobutene

Two new approaches for synthesizing RSiCl, (R = PhC(NtBu)(2)) are reported by the reaction of RSiHCl(2) with bis-trimethyl silyl lithium amide and N-heterocyclic carbene respectively. In the former method silylene is produced in 90% yield. The silylene was treated with biphenyl alkyne to afford the disilacyclobutene system. This is a rare example of two five-coordinate silicon centers arranged adjacent to each other in a four-membered ring. Furthermore, we fluorinated the four-membered ring by trimethyltin fluoride to obtain the fluoro substituted disilacyclobutene.

Novel diaminoaluminum halides and a diaminoaluminum hydride: 1,3,2-Diazaalumina-[3]ferrocenophanes

The dilithiated derivative 2 of 1,1′-bis(trimethylsilylamino)ferrocene ( 1) reacts with the pyridine adducts of the aluminum trihalides AlX 3 (X = Cl, Br, I) to give the respective 1,3,2-diazaalumina-[3]ferrocenophanes ( 4b, c, d) as pyridine adducts. The fluoride 4a could not be obtained in this way. The reaction of 1,1′-bis(trimethylsilylamino)ferrocene ( 1) with the dimethyl(ethyl)amine- or pyridine adduct of aluminium trihydride gave the 1,3,2-diazaalumina-[3]ferrocenophanes ( 5) and ( 6) as the amine and pyridine adducts, respectively. Treatment of 5 with trimethyltin fluoride afforded the adduct 7 with an Al–F function. Addition of pyridine converted 7 into the desired pyridine adduct of the fluoride ( 4a). The molecular structures of the pyridine adducts 4a, 4b, 4c and 6 were determined by X-ray analysis. The pyridine is in the trans-position relative to the N–Si bond vectors, and temperature dependent solution-state NMR spectra prove that prominent structural features are retained in solution.

On the reaction of 4-substituted trimethyltin aromatics with perchlorylfluoride

To evaluate the suitability of [ 18F]perchorylfluoride [ 18F]FClO 3 as an electrophilic fluorination agent for the preparation of radiopharmaceuticals, the reactivity non-radioactive FClO 3 towards 4-substituted trimethyltin aromatic compounds was studied. Contrary to the expectation, an electrophilic fluorination of the aromatic nucleus did not occur. The reaction of perchlorylfluoride with aromatic trimethylstannyl compounds resulted in the formation of trimethyltin fluoride and the respective destannylated aromatics in variable yields.

Stepwise fluorination of [MeAlN(2,6- i-Pr 2C 6H 3)] 3 using trimethyltin fluoride as fluorinating agent

The fluorination of [MeAlN(2,6- i-Pr 2C 6H 3)] 3 1 using 1 and 2 eq., respectively, trimethyltin fluoride leads to the mono- and difluoro compounds, [FAl(MeAl) 2(N(2,6- i-Pr 2C 6H 3)) 3]·2THF 2 and [(FAl) 2MeAl(N(2,6- i-Pr 2C 6H 3)) 3]·3THF 3, where each methyl group can be selectively exchanged for terminal fluorine atoms (AlF). The reaction of 1 and 3 eq. of trimethyltin fluoride leads to the trifluoro compound [FAlN(2,6- i-Pr 2C 6H 3)] 3·3THF 4 and [Me 2SnN(2,6- i-Pr 2C 6H 3)] 2 5 as a by-product. The core of compound 5 consists of a tin–nitrogen four-membered Sn 2N 2 ring.

Conversion of Alkyltantalum Chlorides to Fluorides Using Trimethyltin Fluoride as a Fluorinating Agent. Crystal Structures of (p-MeC6H4CH2)3TaF2, (Me3SnCl·Me3SnF·TaF5)n, (Me3Si)2CHTaCl4, {(Me3Si)2CHTaCl4·[(Me3Si)2CH]2Ta2Cl6(μ2-O)}, and (Me3Si)2CHTaF4

The reactions of alkyltantalum chlorides with trimethyltin fluoride were found to be highly dependent on the number of organic ligands on tantalum as well as on the electronic and the steric nature...

ChemInform Abstract: Trimethyltin Fluoride: A New Fluorinating Reagent for the Preparation of Silicon Fluorides.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Trimethyltin fluoride: A new fluorinating reagent for the preparation of silicon fluorides

A new fluorinating reagent for the preparation of silicon fluorides is described. The preparation of Me 2SiF 2, (CH 2CH)MeSiF 2, EtSiF 3, CH 2CHSiF 3 n-PrSiF 3, n-HexSiF 3 (Hex = C 6 H 13) and PhSiF 3 using Me 3SnF is reported. The products are formed in high yield. The resulting Me 3SnCl can be easily recovered and again converted to the fluorinating reagent.

Aminodimethylalanes (R1R2NAlMe2) as Useful Synthetic Precursors of Aminoalane Difluorides Using Trimethyltin Fluoride: Crystal Structures of (2,6-i-Pr2C6H3)N(SiMe3)AlMe2 and (2,6-i-Pr2C6H3)N(SiMe3)AlF2

Aminodimethylalanes R1R2NAlMe2 (R1 = 2,6-i-Pr2C6H3, 2,6-Me2C6H3; R2 = SiMe3, Si(i-Pr)Me2, Si(t-Bu)Me2, Si(2,4,6-Me3C6H2)Me2) are prepared in high yield via reaction of the respective amine R1R2NH with trimethylaluminum in n-hexane. Further reaction of (2,6-i-Pr2C6H3)N(SiMe3)AlMe2 with 2 equiv of trimethyltin fluoride in toluene affords the aminoalane difluoride (2,6-i-Pr2C6H3)N(SiMe3)AlF2. An X-ray structural determination of (2,6-i-Pr2C6H3)N(SiMe3)AlMe2 shows it to be dimeric with bridging methyl and terminal amino groups. The aminoalane difluoride (2,6-i-Pr2C6H3)N(SiMe3)AlF2 is trimeric with a six-membered alternating aluminum−fluorine ring. Terminal fluorine atoms are located above and below the ring. Reactions of aminoalanes R1R2NAlMe2 with 2 equiv of trimethyltin fluoride in THF yield the monomeric THF adducts R1R2NAlF2·THF.

Trimethyltin Fluoride: A New Fluorinating Reagent for the Preparation of Organometallic Fluorides

Trimethyltin Fluoride: A New Fluorinating Reagent for the Preparation of Organometallic Fluorides

Solid-state 119Sn NMR studies of coordination in triorganyltin fluorides

High-resolution 119Sn spectra of solid trimethyltin fluoride (I), tri-isobutyltin fluoride (II), and triphenyltin fluoride (III) show that all the compounds are five-coordinate in the solid state, with the 119Sn nucleus apparently equally coupled to two fluorines. In contrast, the spectrum of trimesityltin fluoride (IV) indicates, in conformity with X-ray results, that the tin is four-coordinate and couples to only one fluorine, but that there are two molecules in the asymmetric unit.

Reaktive E =C (p—p)π-Systeme, X Darstellung und Reaktivität von Perfluor-3-phosphapent-2-en / Reactive E = C (p-p)π-Systems, X Preparation and Reactivity of Perfluoro-3-phosphapent-2-ene

Abstract Perfluoro-3-phosphapent-2-ene F5C2 P =C (F )CF3 (1) has been prepared for the first time by thermal elimination of trimethyltin fluoride Me3SnF from trim ethylstannyl-bis(pentafluoroethyl)- phosphane Me3SnP(C2F5) 2 at 300 °C/10−3 Torr. 1 is found to be less stable than F3CP = CF2 in dilute solution at room temperature, forming several 1,3-diphosphabutane dimers. Reactivity studies accomplished till now include (i) the dienophilicity of 1 in [2+4] cycloaddition reactions with butadiene, 2,3-dim ethylbutadiene, cyclopentadiene, 1,3-cyclohexadiene, 2-methylbutadiene, and 2-methylfuran leading by a concerted mechanism to the Diels-Alder-adducts 2-7 in about 80% yield, (ii) the addition of proton acidic compounds HX (X = OMe, Br, NMe2, NEt2) to the PC double bond affording chiral phosphanes of the type F5C2 P(X)CF(CF3)H [X = OMe (8). Br (9). NMe2 (10). NEt2 (11)]. thus proving a stronger polarity δ+P =δ−C for 1 than for F3CP = CF2. New compounds have been characterized by NMR and MS measurements.

The crystal and molecular structure of trimethyltin chloride at 135 K. A highly volatile organotin polymer

Abstract : Trimethyltin chloride is the key starting material in the laboratory synthesis of the trimethyltin derivatives most subject to study. It is an article of commerce, and has itself been extensively studied by a great variety of spectroscopic and physical methods. There in the literature starting in 1970 a trail of oft referenced private communications which describe a yet unpublished X-ray structure which is incorrect. In addition, the structure of the analogous triphenyltin chloride, which is monomeric at ambient temperature, is said to undergo a change on cooling to a chlorine bridged polymer, but this suggestion is based upon NQR data a 77K which cannot be reproduced. The structure of the homologous trimethyltin fluoride cannot be solved because of disorder, and thus the widely-quoted bridging halide structures for R3SnX compounds are being confirmed here in there case of the title compound for the first time. Solid trimethyltin chloride at 135K is associated through bent chlorine bridges into a one-dimensional polymer containing non-planer C3Sn moieties in a distorted, axially-most electronegative, trigonal bipyramid at tin. (Author)

N.M.R. investigation of molecular motions in trimethyltin fluoride

Molecular motions of trimethyltin fluoride in the solid state have been studied by continuous wave and pulsed n.m.r. methods. The trimethyltin group rotates about its chain axis at high temperatures. This result with relatively free methyl group rotation even at 77 K supports the previously proposed structure in which there are parallel, planar trimethyltin groups.

Vibrational Anisotropy and Gol'danskii–Karyagin Effect in Trimethyltin Fluoride

The vibrational anisotropy of the tin atom in trimethyltin fluoride has been studied by means of 119Sn Mössbauer spectroscopy in the temperature range 7 < T < 296°K. From the Gol'danskii–Karyagin effect asymmetry of the doublet spectrum, it is inferred that while in the low-temperature limit the metal-atom vibrations are essentially isotropic, at room temperature the difference in the mean-square amplitudes of vibration parallel and perpendicular to the (nearly) threefold symmetry axis defined by the ···F···Sn···F framework, is given by 〈x‖2〉 − 〈x⊥2〉 = − 3.41 × 10−18cm2. The infrared data at room and liquid-nitrogen temperature in the 600–450-cm−1 region are consistent with a small departure from true C3υ symmetry for this molecule, and it is shown that the assumption of an oblate charge distribution about the metal atom (Vzz positive) with an asymmetry parameter η ∼ 0 is only valid in the first approximation. Using free-tin-atom masses and the high-temperature limiting slope of the area under each component of the Mössbauer spectrum doublet, it is possible to calculate a Mössbauer temperature for the π and σ transitions, which for trimethyltin fluoride are 105 ± 2°K and 114 ± 2°K, respectively.

The reactivity of metal—metal bonds VIII. A comparative study of the SiFe, GeFe and SnFe bonds, and some further reactions of the SnMn bond

The reactions of (CH 3) 3SnMn(CO) 5 with perfluoropropene, perfluoro-2-butyne and perfluorocyclobutene are described. Similar reactions of (CH 3) 3MFe(CO) 2(π-C 5H 5) (M = Si, Ge, or Sn) with perfluorocyclobutene, perfluoro-2-butyne, and 3,3,3-trifluoropropyne are described, leading to the characterization of insertion products of the types (CH 3) 3M(CF 3)CC(CF 3)Fe(CO) 2(π-C 5H 5) and (CH 3) 3MC 2H(CF 3)Fe(CO) 2(π-C 5H 5). When M = Sn, other products formed by the elimination of trimethyltin fluoride from 1/1 insertion products, are also formed. The mechanisms of these reactions appear to involve four-centred type transition species.