A Stable Neutral Stannaaromatic Compound: Synthesis, Structure and Complexation of a Kinetically Stabilized 2-Stannanaphthalene (original) (raw)
Related papers
Synthesis and properties of a stable 6-stannapentafulvene
Chemical Communications, 2005
All experiments were performed under an argon atmosphere unless otherwise noted. Solvents used for the reactions were purified by The Ultimate Solvent System (GlassContour Company). 1 1 H NMR (300 MHz), 13 C NMR (76 MHz), and 119 Sn NMR (111 MHz) spectra were measured in CDCl 3 or C 6 D 6 with a JEOL JNM-AL300 spectrometer. In 1 H NMR, signals due to CHCl 3 (7.25 ppm) and C 6 D 5 H (7.15 ppm) were used as references, and those due to CDCl 3 (77 ppm) and C 6 D 6 (128 ppm) were used in 13 C NMR. 119 Sn NMR was measured with NNE technique using SnMe 4 as an external standard. Multiplicity of signals in 13 C NMR spectra was determined by DEPT technique. High-resolution mass spectral data were obtained on a JEOL JMS-SX102GC/MS spectrometer. WCC (wet column chromatography) was performed on Wakogel C-200. PTLC (preparative thin-layer chromatography) was performed with Merck Kieselgel 60 PF254 (Art. No. 7747). GPLC (gel permeation liquid chromatography) was performed on an LC-908 (Japan Analytical Industry Co., Ltd.) equipped with JAIGEL 1H and 2H columns (eluent: chloroform or toluene). All melting points were determined on a Yanaco micro melting point apparatus and were uncorrected. Elemental analyses were carried out at the Microanalytical Laboratory of the Institute for Chemical Research, Kyoto University. Tbt(Mes)SnCl 2 was prepared according to the reported procedures. 2 Preparation of 6. To a THF (4 mL) solution of fluorene (102 mg, 0.614 mmol) was added nbutyllithium (1.5 M in hexane, 0.340 mL, 0.510 mmol) at-78 ˚C. After stirring at the same temperature for 1 h, THF (4 mL) solution of Tbt(Mes)SnCl 2 (353 mg, 0.410 mmol) was added to the mixture. After stirring for 3 h at-78 ˚C, the reaction mixture was warmed to room temperature and stirred for 12 h at the same temperature. After removal of the solvent, hexane was added to the residue. The resulting suspension was filtered through Celite , and the solvent was removed. The residue was separated by GPLC (CHCl 3) to afford 6 (304 mg, 0.307 mmol, 75%).
A Kinetically Stabilized Stannanetellone, a Tin−Tellurium Double-Bonded Compound
Organometallics, 2006
All experiments were performed under an argon atmosphere unless otherwise noted. All soluvents were dried by standard methods and freshly distilled prior to use. 1 H NMR (300 MHz), 13 C NMR (75 MHz), 119 Sn NMR (111 MHz) and 125 Te NMR (94 MHz) spectra were measured in CDCl 3 or C 6 D 6 with a JEOL JNM AL-300 spectrometer. 1 H and 13 C NMR chemical shifts were recorded in ppm relative to tetramethylsilane (δ = 0) and were referenced internally with respect to the residual proton of the impurity (CHCl 3 : δ = 7.26, C 6 D 5 H: δ = 7.15) and the 13 C resonance of the solvent (CDCl 3 : δ = 77.2, benzene-d 6 : δ = 128.0), respectively. The multiplicity of signals in 13 C NMR spectra was determined by the DEPT techniqe. 119 Sn NMR chemical shifts were referenced with tetramethylstannane (δ = 0) as an external standard. 125 Te NMR chemical shifts were referenced with diphenylditelluride (δ = 450) as an external standard. Fast atom bombardment (FAB) mass spectral data were obtained on a JEOL JMS-700 spectrometer. Electronic spectra were recorded on a JASCO V-570 UV/VIS spectrometer. IR spectra were measured at room temperature on a JASCO FT/IR 460 plus spectrometer. Preparative gel permeation liquid chromatography (GPLC) was performed on an LC-918 apparatus or LC908-C60 (Japan Analytical Industry Co., Ltd.) equipped with JAIGEL 1H and 2H columns (eluent: CHCl 3 or toluene). Wet column chromatography was performed with Wakogel C-200. All melting points were determined on a Yanaco micro melting point apparatus and are uncorrected. Elemental analyses were carried out at the Microanalytical Laboratory of the Institute for Chemical Research, Kyoto University. Tributylphosphine telluride a and 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl bromide (BbtBr) b were prepared according to the reported procedures. Preparation of TitpI. To a THF solution of 2,4-diisopropylphenyl magnesium bromide, prepared from 1-bromo-2,4-diisopropylbenzene (40.0 g, 0.166 mol) and magnesium (4.0 g, 0.165 mol) in 60 mL THF by heating at reflux, was added dropwise a THF (50 mL) solution of 1,3-dichloro-2-iodobenzene (11.3 g, 0.041 mol). The resulting solution was heated at reflux for 4 h, cooled to 0 ˚C, and quenched with THF (50 mL) solution of iodine (12.9 g, 0.051 mol). After an aqueous solution of sodium thiosulfate was added, this mixture was extracted with hexane and dried over anhydrous magnesium sulfate. After the removal of the solvents, the residue was separated with wet column chromatography (SiO 2 , hexane) to yield TitpI (8.4 g, 40%): mp 97.5-101.2 ˚C; 1 H NMR (CDCl 3) δ 1.20 (d, 3 J HH = 6.9 Hz , 6H), 1.3 (d, 3
Green Chemistry, 2016
Materials and Methods All chemicals were purchased from commercial suppliers and were used as received. Common laboratory reagents and compounds were purchased from Sigma Aldrich Corp. (Castle Hill, NSW, Australia) and Merck Millipore Limited (Kilsyth, Victoria, Australia). Flash chromatography was performed using Merck Silica Gel 60, 40-63 μm, code 9385. The 1 H and 13 C NMR spectra were recorded on either a Bruker DPX 300 or a Bruker DPX 400 spectrometer. The 1 H NMR spectra were recorded as solutions in deuterated, base-washed (Na 2 CO 3) chloroform (CDCl 3) with TMS (tetramethylsilane) used as the internal standard reference (δ 0.00 ppm) with the CDCl 3 solvent peak (δ 77.26 ppm) used as the internal standard reference for 13 C NMR spectra. Spectra were also recorded as solutions in deuterated water (D 2 O) where the residual internal solvent peak was used as the standard reference for 1 H NMR spectra. Electrospray ionisation mass spectra (ESI) were recorded on a Micromass Platform II API QMS Electrospray mass spectrometer and all samples were run as methanol (MeOH) solutions unless otherwise indicated. The samples were run in positive (ESI +) mode. Melting points were determined using a Buchi melting point B-545 melting point apparatus and are uncorrected. Microanalyses were performed by The Campbell Microanalytical Laboratory, in Dunedin, New Zealand Synthetic Experimental Procedures The details described below summarise the essential information that is required for input as data into iSUSTAIN in order to allow the analysis of the green chemical attributes. 1,4,7-Tris(p-toluenesulfonyl)-1,4,7-triazacyclononane (Tos 3 tacn) (4) A 3 L Erlenmeyer flask was charged with H 2 O (500 mL), anhydrous K 2 CO 3 (162 g, 1.18 mol) and diethylenetriamine (36.4 g, 0.35 mol) and the solution heated to 90°C while being vigorously stirred using an overhead mechanical stirrer. Tosyl chloride (209.2 g, 1.09 mol) was added in small portions (approximately 20 g, every 10 min). After complete addition, the suspension was stirred for an additional 3 h at 90°C. Solid NaOH (127.2 g, 3.2 mol) was slowly added followed by a solution of tetrabutylammonium bromide (10.4 g, 32.26 mmol) in H 2 O (40 mL) and then toluene (1.6 L). The temperature was maintained at 90°C and a total of 120 mL of 1,2dibromoethane was added in 20 mL aliquots by pipette over 8 h. After the final addition, the reaction mixture was stirred at 90°C for a further 8 h, and subsequently cooled to room temperature with stirring overnight. The resulting white precipitate was collected by
Organometallics, 2003
Novel oligomeric titanasiloxanes have been synthesized in good yields by reaction of sterically demanding organosilanetriols with titanium alkoxides. The silanetriols t Bu 2 (Me 3 -Si)FlSi(OH) 3 (5), (Me 3 Si)FlSi(OH) 3 (6), and MeFlSi(OH) 3 (7) and the titanium alkoxides Ti-(OEt) 4 , Ti(O i Pr) 4 , and Ti(O i Pr) 2 (acac) 2 have been used as starting materials (Fl ) fluorenyl). Quite different structures are obtained by only small modifications of the organic substituents of the substrates. Thus, the condensation reactions result in the formation of the polyhedral titanasiloxanes [ t Bu 2 (Me 3 Si)FlSi] A 1:1 stoichiometry of the starting materials leads to 8 and 12 in quantitative yield, while 9-11 are isolated in minor quantities. If the appropriate substrate ratio is used, the latter compounds can also be obtained in high yields. All titanasiloxanes have been characterized by X-ray crystallography, NMR, IR, and elemental analysis. . (1) (a) Abbenhuis, H. C. L.; Krijnen, S.; van Santen, R. A. Chem. Commun. 1997, 331. (b) Crocker, M.; M. Herold, R. H.; Orpen, A. G. Abbenhuis, H. C. L.; van Santen, R. A.; Thiele, S. K.-H.; van Tol, M. F. H. Organometallics 1998, 17, 5222. (f) Duchateau, R.; Cremer, U.; Harmsen, R. J.; Mohamoud, S. I.; Abbenhuis, H. C. L.; van Santen, R. A.; Meetsma, A.; Thiele, S. K.-H.; van Tol, M. F. H.; Kranenburg, M. Organometallics 1999, 18, 5447. (g) Gao, X.; Wachs, I. E. Catal. Today 1999, 51, 233. (h) Voigt, A.; Murugavel, R.; Montero, M. L.; Wessel, H.; Liu, F.-Q.; Roesky, H. W.; Usón, I.; Albers, T.; Parisini, E. Voigt, A.; Walawalkar, M. G.; Roesky, H. W. Chem. Rev. 1996, 96, 2205. (b) Hursthouse, M. B.; Hossain, A. Polyhedron 1984, 3, 95. (c) Hossain, M. A.; Hursthouse, M. B.; Mazid, M. A.; Sullivan, A. C. Chem. Commun. 1988, 1305. (d) Hossain, M. A.; Hursthouse, M. B.; Ibrahim, A.; Mazid, M.; Sullivan, A. C.
Journal of Molecular Structure, 1999
Crystallographic structural refinements of the cubic (I) and triclinic (II) forms of [(n-C 4 H 9) 4 N] 3 [Sc(NCS) 6 ] have been carried out by means of three-dimensional single-crystal X-ray diffractometry. The cubic form crystallizes in space group Pa3 (No. 205, Z 8) and the triclinic form crystallizes in P1 (No. 2, Z 2). The respective lattice constants are a 24.630(4) Å (I) and a 12.232(2), b 12.655(3), c 22.337(4) Å , a 90.48(3), b 90.92(3), g 96.73(3)Њ (II). A full-matrix least-squares refinement program yielded final reliability (R) factors of 0.088 and 0.061 based on 1078 and 4660 unique reflections, respectively. In both complexes, the molecular units consist of three separate cationic tetra-n-butylammonium groups and an independent hexakisisothiocyanatoscandium anionic group. The n-butyl ligands are coordinated tetrahedrally to the ammonium-nitrogen atoms and the near linear six thiocyanate ligands coordinate octahedrally through the nitrogen atoms to the scandium metal center atoms. Characterizations include physical property determinations and spectrometric identifications employing I.R., 1 H and 13 C NMR and X-ray powder analyses. Selected bond distances and angles as well as syntheses and peripheral studies are presented and discussed.
Mild and Rapid Method for the Generation of ortho-(Naphtho)quinone Methide Intermediates
Organic Letters, 2012
Unless otherwise noted, reactions were carried out under argon atmosphere, in flame dried, three-neck, with magnetic stirring. Organic solutions were concentrated by rotary evaporation at 23-40 °C under 15 Torr. Melting points were taken on a Büchi 510 apparatus and are uncorrected. 1 H and 13 C NMR spectra were measured in CDCl 3 or DMSO-d 6 on a 250 or 400 MHz Brüker spectrometer. 1 H chemical shifts are reported in ppm from an internal standard TMS, residual chloroform (7.26 ppm) or DMSO-d 6 (2.50 ppm). 13 C NMR chemical shifts are reported in ppm from an internal standard TMS, residual chloroform (77.00 ppm) or DMSO-d 6 (39.43 ppm). High resolution ESI mass spectra were measured on a ThermoFisher Scientific Orbitrap XL system. Low resolution ESI spectra were measured with an Agilent 1100 LC-MS/MS spectrometer. IR spectra were acquired on a Perkin-Elmer 257 or a Perkin-Elmer GX FTIR spectrophotometer as liquids between sodium chloride discs or KBr discs and are reported in wave numbers (cm-1). Elemental analyses were performed on a Carlo Erba 1106 elemental analyser. Analytical thin layer chromatography (TLC) was performed with TLC plates (Merck 70-230 mesh silica gel). Visualization was done under a 254 nm UV light source and generally by immersion in acidic aqueous-ethanolic vanillin solution, or in potassium permanganate (KMnO 4), followed by heating using a heat gun. Purification of reaction products was generally done by dry-column flash chromatography 1 using Μerck silica gel 60 and/or flash chromatography 2 using Carlo Erba Reactifs-SDS silica gel 60. 2. Materials Solvents, reagents and catalysts were used as received from the manufacturers (Aldrich, Acros, Fluka, and Alfa-Aesar) except for tetrahydrofuran, dichloromethane, ethanol, methanol, ethyl acetate, hexane and toluene that were purified and dried according to recommended procedures. S3 3. Experimental Procedures (2-{[tert-Butyl(dimethyl)silyl]oxy}-1-naphthyl)methanol (3b) To a solution of NaBH 4 (317 mg, 12 mmol) in MeOH (20 mL) was added 2b 3 (2.0 g, 10 mmol) in MeOH (10 mL). The mixture was stirred at room temperature for 6 h. MeOH was then removed and the resulting crude re-dissolved in EtOAc (30 mL) and washed with brine (10 mL). The organic layer was dried with sodium sulphate, filtered and the solvent was removed in vacuo. The residue was purified by drycolumn flash chromatography (5 % ethyl acetate in hexane) gave 3b (1.8 g, 89%) as a colourless oil. R f = 0.25 (10% ethyl acetate in hexane). 1 H NMR (250 MHz, DMSO
Synthesis and Evaluation of a Pseudocyclic Tristhiourea-Based Anion Host
The Journal of Organic Chemistry, 2007
Binding Studies with 10…………………………………………………………………S37-S43 S3 General Procedures All operations with air-and moisture-sensitive compounds were performed by Schlenk techniques under Argon atmosphere. All solvents were of analytical grade or better. THF was distilled over sodium/ benzophenone; other solvents were purchased as anhydrous. 1 H and 13 C NMR spectra were recorded on 400 or 500 MHz spectrometers in CDCl 3 and DMSO d 6. 1 H signals are referenced to the residual proton (7.26 ppm for CDCl 3 and 2.50 ppm for DMSO d 6) of a deuterated solvent and for 13 C NMR spectra, the signals of CDCl 3 (77.0 ppm) and DMSO-d 6 (40.45 ppm) were used as references. Mass spectra were obtained on a magnetic sector spectrometer, equipped with CI, EI and FAB probes and on quadropole ion trap spectrometer, equipped with ESI probe. HRMS spectra were obtained on MALDI-TOF and ESI Q-TOF spectrometers. IR spectra were obtained on a FTIR spectrometer. UV-vis spectra were obtained on an UV-VIS-NIR scanning spectrometer equipped with double monochromators. 1D Fluorescence and 3D EEM spectra were obtained on a spectrofluorimeter equipped with excitation and emission double monochromators. The progress of reactions was monitored by TLC on a silica gel and visualized by UV-light and/or in an iodine development chamber and by HPLC with diode array detector. Flash chromatography was carried out on a silica gel (0.040-0.063 mm). tert-Butyl-2-(2-aminoethoxy)ethylcarbamate (1). A suspension of NaOH (1.24 g, 31.0 mmol) in methanol (210 mL) was heated to reflux to allow dissolution. This solution was cooled to RT and solid 3-oxapentane-1,5-diamine dihydrochloride (3.09 g, 17.55 mmol) was added under argon. The resultant mixture was stirred for 30 min and a solution of di-tert-butylcarbonate (1.83 g, 10.53 mmol) in dry THF (80 mL) was added dropwise at RT. The reaction mixture was stirred overnight at RT and evaporated to give a white solid residue. The crude product was extracted with CH 2 Cl 2 (3 × 350 mL; each extraction was performed for at least 6 h). Organic fractions were pulled together and evaporated to yield 1 as a yellow oil (1.76 g, 82%).
Reactive trityl derivatives: stabilised carbocation mass-tags for life sciences applications
Organic & Biomolecular Chemistry, 2008
Instrumentation. 500 MHz 1 H and 125.7 MHz 13 C NMR spectra were recorded on a Bruker DRX-500 spectrometer and referenced to CDCl 3 (7.25 ppm) and DMSO-d 6 (2.50 ppm). 1 H-13 C gradient-selected HMQC and HMBC spectra were obtained by using 2048 (t 2 )×256 (t 1 ) complex point data sets, zero filled to 2048 (F 2 )×1024 (F 1 ) points. The spectral widths were 13 ppm and 200 ppm for 1 H and 13 C dimensions, respectively. HMBC spectra were measured with 50 ms delay for evolution of long-range couplings. (MA)LDI-TOF mass spectra were obtained using a Voyager Elite Biospectrometry Research Station (PerSeptive Biosystems, Vestec Mass Spectrometry Products) in a positive ion mode. EI-TOF HRMS and ESI-TOF HRMS spectra in positive ion mode were obtained using Micromass LCT reflection TOF mass spectrometer. Analytical thin-layer chromatography was performed on the Kieselgel 60 F 254 precoated aluminium plates (Merck), spots were visualised under UV light (254 nm). Column chromatography was performed on silica gel (Merck Kieselgel 60 0.040-0.063 mm). Reagents and solvents. Reagents obtained from commercial suppliers were used as received. 4-Hydroxy-4′-methoxybenzophenone (3), [1] Pd(PPh 3 ) 4 , tert-butyl 6-bromohexanoate, were prepared as described. Solvents were mainly HPLC grade and used without further purification unless otherwise noted. DCM was always used freshly distilled over CaH 2 . THF was distilled over powdered LiAlH 4 or over sodium benzophenone ketyl and stored over 4Å molecular sieves under nitrogen. DMF was freshly distilled under reduced pressure. OH O O O O O Cl(CH 2 ) 3 CO 2 Bu t MeONa / HMPA 75%