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1.
Renji Okazaki Akihiko Ishii Nobuo Fukuda Hiroyuki Oyama Naoki Inamoto 《Tetrahedron letters》1984,25(8):849-852
Thermal and photochemical reactions of the title compound gave benzothiolane in high yield; the reaction with free radicals also afforded along with some other products. 相似文献
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Lijin Qin Hongmeng Cui Dapeng Zou Jingya Li Zhiwu Zhu Yusheng Wu 《Tetrahedron letters》2010,51(33):4445-11097
Pd-catalyzed cross-coupling reaction of tert-butyl carbamate with various aryl(Het) halides with Cs2CO3 as base in 1,4-dioxane as solvent was investigated, which resulted in the formation of the desired compounds in moderate to excellent yields. 相似文献
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René T. Boeré Lai-Yoong Goh Chwee Ying Ang Hiu Fung Lau Tracey L. Roemmele 《Journal of organometallic chemistry》2007,692(13):2697-2704
A rational synthesis for 5-tert-butyl-3-cyano-1-(1,2,3,5-dithiadiazolyl)benzene, which was first observed from thermal cleavage of the bis-dithiadiazolyl, has been developed. Voltammetry and electron paramagnetic resonance (EPR) spectra for this radical are reported and its X-ray structure is described. Despite the bulky tBu substituent, the cyano supramolecular synthon is still able to maintain links to a single neighbouring sulfur atom of the S2 unit, as previously observed in cyano-substituted dithiadiazolyls. In the η2 complex with CpCr(CO)2, no such interactions are observed; the nitrile group forms a centrosymmetric dimer through weak contacts with the para H atom on the aryl ring of the partner molecule. This behaviour is contrasted to similar complexes of less bulky dithiadiazolyls, where intermolecular interactions are retained in the crystalline lattice. 相似文献
5.
The addition of Grignard reagents to chiral trifluoromethyl tert-butyl sulfinimine-ethanol adducts affords protected trifluoromethylamines in high yields with good to excellent diastereoselectivities. The stereochemical outcome of the addition is opposite to that expected via a chelation controlled transition state. 相似文献
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β-Tetra(tert-butyl)porphyrin was prepared from 2-dimethylaminomethyl-4-tert-butylpyrrole and converted into porphine, the mother compound of porphyrins, in 64% yield. The dealkylation smoothly proceeded in aqueous sulfuric acid over 15 min at 190 °C under nitrogen. 相似文献
7.
Barbara Mendrek 《European Polymer Journal》2009,45(7):1979-5086
Star polymers with different numbers and lengths of poly(tert-butyl acrylate) (PTBA) arms were obtained via atom transfer radical polymerization. Aliphatic alcohols with different number of hydroxyl groups varying from 3 to 6 and calix[4]arenes based on pyrogallol with 12 and 16 phenol groups were transformed to bromoester derivatives to prepare multifunctional ATRP initiators used as the cores of the stars. The star polymers were characterized by GPC with refractive index, multiangle laser light scattering and viscosimetric detectors. The molar masses of the stars reached 70,000 g/mol and the molar mass dispersities did not exceed 1.2. To elucidate the compact structure of the stars, their true molar masses were determined by GPC with triple detection (RI-MALLS-Visco) and compared with the apparent molar masses obtained from the calibration with linear poly(tert-butyl acrylate) standards. The intrinsic viscosities of the PTBA stars of the same molar mass decreased with the number of star arms but were always lower than the intrinsic viscosities of the analogue linear PTBA polymers. The values of the branching ratio g′ decreased with increasing number of arms indicating more compact structure of stars. The branching ratio g′ was correlated to the empirical predictions. 相似文献
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This paper reports the synthesis of 4-arm poly(tert-butyl acrylate) stars of different molar masses up to 106 g/mol by the “core-first” method using ATRP. All obtained stars have a monomodal and narrow molar-mass distribution (<1.2).The dilute-solution properties of these star polymers were investigated in good solvents (tetrahydrofuran and acetone). Gel permeation chromatography and dynamic and static light scattering were used to measure the hydrodynamic properties including intrinsic viscosity [η], radius of gyration Rg, hydrodynamic radius Rh, second virial coefficient A2 and diffusion coefficient D0. These data were used to establish relationships between these parameters and the molar mass of 4-arm poly(tert-butyl acrylate) stars. The branching parameters g and g′ and the shape factor ρ were calculated for all obtained star polymers. 相似文献
9.
Julia E. Barker 《Tetrahedron letters》2005,46(40):6805-6808
Mononuclear (Me3TACN)MnX3 compounds, where X is Cl−, Br−, or N3−, and Me3TACN is 1,4,7-N,N′,N″-trimethyl-1,4,7-triazacyclononane, have been tested for catalyzing both sulfide oxygenation and styrene epoxidation by tert-butyl hydroperoxide (TBHP) and display turnover frequencies (TOF) up to 200 h−1 at room temperature. Sulfoxides or sulfones may be produced selectively by varying reaction conditions. Product distribution from the oxygenation reactions of ethyl phenyl sulfide, 2-chloroethyl phenyl sulfide, and styrene is consistent with a mechanism involving an early single-electron transfer (SET) step. 相似文献
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The liquid–liquid equilibria for binary systems of tert-amyl ethyl ether (TAEE) + water, isopropyl tert-butyl ether (IPTBE) + water and di-sec-butyl ether (DSBE) + water are analytically determined in the temperature range 278.65–358 K. Additionally, tie-lines for six ternary systems of TAEE, IPTBE and DSBE with methanol and water or with ethanol and water are also measured at 298.15 K. All the measured binary and ternary data were correlated with the NRTL and UNIQUAC model. The reliability of the experimental tie-line data for ternary systems was ascertained by using the Othmer–Tobias correlation. 相似文献
11.
Suqing Zheng 《Tetrahedron letters》2009,50(31):4532-999
A phosphine-catalyzed [3+3] annulation reaction of modified tert-butyl allylic carbonates with various alkylidenemalononitriles to form cyclohexenes was developed. The use of protic solvent is crucial in this reaction. When non-polar solvent, toluene or xylene, was used, only non-cyclized product was obtained. 相似文献
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Chunxiao Wen Jiawei Wu Yingcong Ou Yulin Huang Kun Zhang Qian Chen 《Tetrahedron letters》2018,59(40):3609-3611
A novel and efficient TBHP/TBAI-mediated oxidation of thiophenols is described. The reactions proceeded smoothly to give tert-butyl arylsulfinates in up to 82% yield with good functional group compatibility under mild conditions. 相似文献
14.
Reaction of a variety of tert-butyl carbamates under glycosylation conditions gives rise to anomeric 2-deoxy-2-amino sugar carbamates in a good to excellent yields. The reaction exhibits good tolerance to several common protecting groups, and has been used to generate unnatural glycopeptide building blocks. 相似文献
15.
A variety of commercially available alcohols were converted to their bis-(tert-butyl) protected mono-phosphate pro-drugs. The improved procedure uses the unique combination of imidazole·hydrochloride and imidazole as the activator to suppress the formation of undesired phosphonate by-product frequently encountered with the bis-(tert-butyl) phosphoramidite reagents. The new activation procedure eliminates the need to use excess reagents. 相似文献
16.
Bruno Therrien Author Vitae 《Journal of organometallic chemistry》2011,696(3):637-651
This review covers the rich coordination chemistry of 2,4,6-tri(pyridyl)-1,3,5-triazine ligands. These polypyridyl derivatives have been coupled to transition metals and lanthanides, and the complexes obtained have been used in various fields such as luminescent materials, for the preparation of coordination polymers and networks as well as for the synthesis of discrete metalla-assemblies. The synthetic and structural aspects of the different isomers of 2,4,6-tri(pyridyl)-1,3,5-triazine are presented, and a survey of their coordination chemistry is given. 相似文献
17.
Protonation of the reactive intermediates produced in the reaction between tert-butyl isocyanide and dialkyl acetylenedicarboxylates by aromatic carboxylic acids leads to vinylnitrilium cations, which undergo nucleophilic reaction with conjugate bases of the carboxylic acids to produce dialkyl (E)-2-[(benzoyloxy)(tert-butylimino)methyl]-2-butenedioates and this intermediate rearranges to the dialkyl (E)-2-{[benzoyl(tert-butyl)amino]carbonyl}-2-butenedioate derivatives. 相似文献
18.
Ji-Eun Kang 《Tetrahedron letters》2005,46(43):7431-7433
AuCl3 efficiently catalyzes cyclization of tert-butyl allenoates into γ-butenolides. Advantage of directly using allenic ester precursor instead of corresponding acid is demonstrated in the synthesis of a variety of 2,4-disubstituted butenolides. A low catalyst loading and mild reaction condition makes this process an attractive alternative over conventional methods using strong Lewis acids. 相似文献
19.
Ronald Grigg Christian Lofberg Visuvanathar Sridharan Andrew Derrick 《Tetrahedron》2009,65(4):849-4087
Ir-catalysed alkylation of tert-butyl cyanoacetate with a range of substituted benzyl and heteroaryl alcohols under solvent free conditions afforded the corresponding monoalkylated products in moderate to high yields. 相似文献
20.
Scott D. Kuduk Robert M. DiPardo Ronald K. Chang Christina Ng Mark G. Bock 《Tetrahedron letters》2004,45(35):6641-6643
Addition of Grignard reagents to chiral tert-butyl sulfinimines derived from pyridine 2-carboxaldehyde affords protected 2-pyridyl amines in high yields and diastereoselectivities. The sense of chiral induction is opposite to that predicted via a chelation-controlled transition state. 相似文献