Cyclic Alkyl(aryl)boranes for 1,1-Carboboration of Monoalkynyltin Compounds

2013 ◽  
Vol 68 (5-6) ◽  
pp. 493-502 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Peter Thoma ◽  
Wolfgang Milius
Keyword(s):  
Solid State ◽  
High Selectivity ◽  
Ring Expansion ◽  
Membered Ring ◽  
Reaction Products ◽  
State Structure ◽  
Alkyl Aryl ◽  
X Ray ◽  
X Ray Crystallography ◽  
Nmr Techniques

Two cyclic alkyl(aryl)boranes, a 1-bora-indane derivative 1, and a tricyclic derivative 4, containing the boron atom in a six-membered ring, were structurally characterized by NMR techniques in solution. The solid-state structure of the 1-bora-indane 1 was determined by X-ray crystallography. The reactivity of these cyclic alkyl(aryl)boranes towards monoalkynyltin compounds, Me3Sn-C≡C-Me and Me3Sn-C C-Fc (Fc=ferrocenyl), was studied using multinuclear magnetic resonance methods (1H, 11B, 13C, 119Sn NMR). Novel alkenylboranes were formed by 1,1-carboboration reactions. This process involves an expansion of both five- and six-membered rings. Insertion into the respective B-C(aryl) bond was preferred with high selectivity. In the case of the six-membered ring in 4, the ring expansion to seven-membered rings proved to be readily reversible, and the thermodynamically stable reaction products were formed by ring contraction and concomitant transfer of the exocyclic B-nPr group

Synthesis and structural characterization of a magnesium phthalocyanine(3–) anion

2012 ◽  
Vol 16 (01) ◽  
pp. 154-162 ◽  
Author(s):  
Edwin W.Y. Wong ◽  
Daniel B. Leznoff
Keyword(s):  
Absorption Spectrum ◽  
Solid State ◽  
Single Crystal ◽  
Structural Characterization ◽  
Heterometallic Complex ◽  
State Structure ◽  
Solid State Structure ◽  
X Ray ◽  
X Ray Crystallography

The reduction of magnesium phthalocyanine (MgPc) with 2.2 equivalents of potassium graphite in 1,2-dimethoxyethane (DME) gives [K2(DME)4]PcMg(OH)(1) in 67% yield. Compound 1 was structurally characterized using single crystal X-ray crystallography and was found to be a monomeric, heterometallic complex consisting of a μ3-OH ligand that bridges a [MgIIPc3-]- anion to two potassium cations solvated by four DME molecules. An absorption spectrum of 1 confirms the Pc ligand is singly reduced and has a 3–charge. The solid-state structure of 1 does not indicate breaking of the aromaticity of the Pc ligand. Compound 1 is only the second Pc3- complex and the first reduced MgPc to be isolated and structurally characterized.

The two solid-state conformations of nefopam methiodide, a quaternary ammonium salt of the analgesic drug

1990 ◽  
Vol 68 (7) ◽  
pp. 1128-1134 ◽  
Author(s):  
Robert Glaser ◽  
André Michel ◽  
Marc Drouin
Keyword(s):  
Solid State ◽  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
State Structure ◽  
X Ray Diffraction ◽  
Analgesic Drug ◽  
X Ray ◽  
Positional Disorder ◽  
X Ray Crystallography

The solid-state structure of nefopam methiodide, a quaternary ammonium salt of nefopam hydrochloride (a non-narcotic analgesic drug), has been determined by single crystal X-ray diffraction analysis. Nefopam methiodide gives crystals belonging to the monoclinic P21/c space group and, at 298 K, a = 10.001(1), b = 9.928(1), c = 17.598(1) Å, β = 94.41(1)°, V = 1742.2(2) Å3, Z = 4, R(F) = 0.086, and Rw(F) = 0.108. Due to disorder, the boat (flattened chair) and twist-chair (flattened chair) conformations of the 2,5-benzoxazocine eight-membered ring were both observed in the crystal with 55:45 occupancy, respectively. Positional disorder was also observed for the iodide counterion, which showed occupancies of 81:9.5:9.5. Keywords: nefopam, analgesic, X-ray crystallography, conformation.

Solid-state structure of NH-pyrazolium hydrochlorides and hydrobromides by X-ray crystallography and CPMAS NMR

1997 ◽  
Vol 415 (1-2) ◽  
pp. 81-92 ◽  
Author(s):  
Concepción Foces-Foces ◽  
Lourdes Infantes ◽  
Rosa Marı́a Claramunt ◽  
Concepción López ◽  
Nadine Jagerovic ◽  
...  
Keyword(s):  
Solid State ◽  
State Structure ◽  
Solid State Structure ◽  
X Ray ◽  
X Ray Crystallography

Self-Assembly of a Charge-Neutral Molecular Square

2004 ◽  
Vol 57 (5) ◽  
pp. 409 ◽  
Author(s):  
Mohammad Akbar Ali ◽  
Paul V. Bernhardt ◽  
Chong Lee Kiem ◽  
Aminul Huq Mirza
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Self Assembly ◽  
1H Nmr Spectroscopy ◽  
The Self ◽  
State Structure ◽  
X Ray ◽  
X Ray Crystallography ◽  
A Charge ◽  
Molecular Square

Complexation of cadmium(II) by the ditopic (bis-tridentate) thiocarbazone ligand 1,5-bis(6-methyl-2-pyridyl- methylene)thiocarbonohydrazide, H2L1, results in the self-assembly of a charge-neutral 2 × 2 molecular grid, [Cd4(L1)4], comprising four metals and four ligands in an interlocked cyclic array. The solid-state structure of this tetramer has been established by X-ray crystallography and in solution by 1H NMR spectroscopy. The presence of lower molecular weight oligomers was identified by both NMR and ESI-MS.

Alkoxide-functionalized cyclopentadienyl complexes of yttrium containing a two-carbon tether

2002 ◽  
Vol 80 (10) ◽  
pp. 1285-1292 ◽  
Author(s):  
Roland AL Gendron ◽  
David J Berg ◽  
Tosha Barclay
Keyword(s):  
Solid State ◽  
Key Words ◽  
Intramolecular Cyclization ◽  
Thermal Reaction ◽  
Chloride Complex ◽  
State Structure ◽  
Reduced Pressure ◽  
X Ray ◽  
X Ray Crystallography ◽  
Cyclopentadienyl Complexes

The ligand C5H4(CH2CH2CArF2OH) (3) (ArF = 3,5-C6H3(CF3)2) was prepared in two steps, from the iodo ester ICH2CH2CO2Me by way of the cyclopentadienyl ester C5H5CH2CH2CO2Me (2), in 55% overall yield. Thermal reaction of 3 with {Y[N(SiMe3)2]2(THF)2(µ-Cl)}2 afforded the neutral chloride complex {η5:η1-C5H4[CH2CH2C(O)(3,5-C6H3(CF3)2)2]}YCl{THF}n (5a: n = 2, 5b: n = 1). Metathesis reactions of 5 with 1 equiv of NaN(SiMe3)2, LiO-2,6-t-Bu2C6H3, and LiCH(SiMe3)2 afforded {η5:η1-C5H4[CH2CH2C(O)(3,5-C6H3(CF3)2)2]}Y{N(SiMe3)2}{THF}n (6), {η5:η1-C5H4[CH2CH2C(O)(3,5-C6H3(CF3)2)2]}Y{O-2,6-t-Bu2C6H3}{THF}n (7), and {η5:η1-C5H4[CH2CH2C(O)(3,5-C6H3(CF3)2)2]}Y{CH(SiMe3)2}{THF}n (8), respectively, (a: n = 2, b: n = 1). Exposure of the bis(THF) solvates to reduced pressure resulted in desolvation to the mono(THF) adducts for 5–8. The solid state structure of 6b was established by X-ray crystallography. In addition, formation of a spirocyclic ether (C4H6CH2CH2C(O)(3,5-C6H3(CF3)2)2 4), obtained by the intramolecular cyclization of ligand 3, was confirmed by X-ray crystallography. Key words: yttrium, organometallic, cyclopentadienyl, X-ray, alkoxide, chelate, alkyl, hybrid ligand, NMR, cyclization.

Silaheterocycles 36 (1). Trichlorovinylsilane, lithium-tert-butyl, and 1,3-enynes: A versatile combination for the competitive formation of silacyclobutanes and silacyclobutenes

2000 ◽  
Vol 78 (11) ◽  
pp. 1445-1458 ◽  
Author(s):  
N Auner ◽  
M Grasmann ◽  
B Herrschaft ◽  
M Hummer
Keyword(s):  
Solid State ◽  
Triple Bond ◽  
Reaction Pathway ◽  
Membered Ring ◽  
State Structure ◽  
Orthorhombic Space Group ◽  
Multiple Bonds ◽  
X Ray ◽  
Tert Butyl ◽  
One Step

Equimolar amounts of trichlorovinylsilane (9), lithium-tert-butyl, and 1,3-enynes were reacted to yield the corresponding isomeric silacyclobutanes and silacyclobutenes competitively. As reaction pathway the mixture 9/tBuLi is discussed to give a silene equivalent, Cl2Si=CHCH2tBu (10), yielding the four-membered ring silacycles by formal [2 + 2] cycloaddition reactions of 10 with the C=C double or the C=C triple bond of the 1,3-enyne. The relative ratio of the products formed depends on the polarity of the multiple bonds in the enyne, which is mainly determined by the substituent pattern. Thus, from the organosubstituted 1,3-enynes R1 C=C-C(R2)=CR3R4 (R1 = Me, Et, SiMe3, Ph; R2 = H, Me, Ph; R3=Me, OMe, Ph; R4=H; and R1C=C-R' (R' = 1-cyclohexenyl, cyclohexanevinylidyne)) and 9/tBuLi the silacyclobutanes 12, 13, and 15 and the silacyclobutenes 14,16-24, and 27 (from 10 and 3-hexyne) are prepared in a one-step synthesis and isolated from the reaction mixtures. The silacyclobutanes and -butenes are thermally stable and can be distilled under vacuo up to temperatures of about 150°C without decomposition. The experimental results are confirmed qualitatively by semiempiric calculations at the AM-1 level and their analysis using FMO theory. The solid state structure of the silacyclobutene 19 (C17H30Cl2Si2) has been determined by single crystal X-ray diffractometry. 19 is orthorhombic, space group P212121, a = 1030.94(2) pm, b = 1244.6(2) pm, c = 1605.5(3) pm, Z = 4.Key words: neopentylsilene, dichloroneopentylsilene, silacyclobutenes, silacyclobutanes, 1,3-enynes.

Vanadium and niobium diamidophosphine complexes and their reactivity

2003 ◽  
Vol 81 (12) ◽  
pp. 1431-1437 ◽  
Author(s):  
Michael P Shaver ◽  
Robert K Thomson ◽  
Brian O Patrick ◽  
Michael D Fryzuk
Keyword(s):  
Coordination Chemistry ◽  
Solid State ◽  
Molecular Nitrogen ◽  
Tridentate Ligand ◽  
State Structure ◽  
Butyl Lithium ◽  
Solid State Structure ◽  
X Ray ◽  
X Ray Crystallography ◽  
Unstable Complex

The tridentate ligand precursors R′P(CH2SiMe2NR′′)2 (R′R′′[NPN]: R′ = Cy, Ph; R′′ = Ph, Mes, Me) were prepared from metathesis reactions of a lithiated amine, chloro(chloromethyl)dimethylsilane, the appropriate 1° phosphine, and n-butyl lithium and were isolated as solvent adducts. Metathesis between CyPh[NPN]Li2(OEt2), 2, and VCl3(THF)3 afforded (CyPh[NPN]VCl)2, 7, whose solid-state structure was established by X-ray crystallography. Reduction attempts of the (R′R′′[NPN]VCl)2 species with KC8 incorporated molecular nitrogen but were complicated by imide formation and ligand decomposition. Metathesis of 2 with NbCl2Me3 afforded the highly unstable complex CyPh[NPN]NbMe3, 15. Attempts to hydrogenate this species were unsuccessful.Key words: vanadium, niobium, metathesis, coordination chemistry, reduction, hydrogenation.

Structural diversity in thallium chemistry: structures of four chlorothallate(III) salts including a novel compound containing three geometrically different anions

1996 ◽  
Vol 74 (8) ◽  
pp. 1490-1502 ◽  
Author(s):  
Margaret Ann James ◽  
Jason A.C. Clyburne ◽  
Anthony Linden ◽  
Bruce D. James ◽  
John Liesegang ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Solid State ◽  
Structural Diversity ◽  
State Structure ◽  
X Ray ◽  
Coordination Numbers ◽  
X Ray Crystallography ◽  
Hydrogen Bonding Networks ◽  
Alkyl Ammonium ◽  
High Coordination

Four new thallium-containing salts with different alkyl ammonium cations have been prepared and characterized by X-ray crystallography: 1: bis(p-toluidinium) pentachlorothallate(III), [CH3C6H4NH3]2 [TlCl5], M = 597.9, monoclinic, P21/c, a = 7.515(2), b = 21.376(6), c = 12.769(2) Å, β = 92.13(2)°, V = 2050(1) Å3, Z = 4, Dcalc = 1.937 Mg m−3, µ = 8.512 mm−1, T = 293(1) K, R = 0.046; 2: 1,5-pentanediammonium pentachlorothallate(III), [NH3(CH2)5NH3] [TlCl5], M = 485.83, orthorhombic, P212121, a = 13.226(2), b = 13.595(2), c = 7.628(2) Å, V = 1371.6(3) Å3, Z = 4, Dcalc = 2.352 Mg m−3, µ = 12.84 mm−1, T = 173(1) K, R = 0.025; 3: pentakis(2-adamantaneammoniumn) bistetrachlorothallate(III) hexachlorothallate(III), [C10H18N]5 [TlCl4]2[TlCl6], M = 1870.75, monoclinic, P21a = 16.466(5), b = 25.985(2), c = 7.724(3) Å, β = 90.14(3)°, V = 3305(2) Å3, Z = 2, Dcalc = 1.880 Mg m−3, µ = 7.978 mm−1, T = 173(1) K, R = 0.056; 4: bis(piperazinium) decachlorodithallate(III) trihydrate, [NH2C4H8NH2]2 [Tl2Cl10]•3H2O, M = 993.62, monoclinic, C2/c, a = 14.154(3), b = 15.445(3), c = 13.228(3) Å, β = 114.44(1)°, V = 2632.7(9) Å3, Z = 4, Dcalc = 2.506 Mg m−3, µ = 13.39 mm−1, T = 173(1) K, R = 0.026. For most of the salts examined, formation of [TlCl5]2− is possible; however, no isolated [TlCl5]2− anions were observed. In most cases, high coordination numbers at thallium were observed (CN = 6), and these can be achieved via formation of anionic chains or through dimerization, giving [Tl2Cl10]4−. Of particular interest is the solid state structure of salt 3 in which there are three geometrically different chlorothallate ions. Extensive hydrogen-bonding networks are observed in each structure. Key words: thallium, thallium(III) chlorides, chlorothallate, hydrogen bonding, alkyl ammonium cations.

Metal complexes of an amine bisphenol with a thiophene side-arm

2010 ◽  
Vol 75 (10) ◽  
pp. 1051-1060 ◽  
Author(s):  
Eero Salminen ◽  
Reijo Sillanpää ◽  
Ari Lehtonen
Keyword(s):  
Solid State ◽  
Nitrogen Atom ◽  
Dimeric Complex ◽  
State Structure ◽  
Molybdenum Complex ◽  
Reaction Conditions ◽  
One Pot ◽  
X Ray ◽  
X Ray Crystallography ◽  
Phenolic Oxygen

Dioxomolybdenum(VI) and oxotungsten(VI) complexes with a new amine bisphenol ligand (H2L) are reported. The ligand which carries a neutral nitrogen atom, two phenolic oxygen atoms and a thiophene side-arm was synthesized by a simple one-pot Mannich reaction. Further reaction with [MoO2(acac)2] yielded a monomeric molybdenum complex [MoO2(L)(MeOH)] (2a) or a dimeric complex [Mo2O2(μ-O)2(L)2] (2b), depending on the reaction conditions. The reaction with a tungsten trisglycolate [W(eg)3] led to the formation of a monomeric compound [WO(eg)(L)] (3). In these complexes, the potentially tetradentate amine bisphenolate dianion coordinates as a tridentate O,N,O donor while the sulfur side-arm donor remains intact. The solid-state structure of 2a was investigated by X-ray crystallography.

Sign in / Sign up

Export Citation Format

Share Document