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21.
An Efficient and Selective Solid State Oxidation of Thiols to Disulfides with Quinolinium Fluorochromate on Silica Gel 总被引:1,自引:0,他引:1
Tajbakhsh Mahmood Mohammadpoor-Baltork Iraj Alimohammadi Kamal 《Monatshefte für Chemie / Chemical Monthly》2003,134(12):1571-1575
Summary. Various kinds of aliphatic (cyclic and acyclic), aromatic, and heterocyclic thiols are converted into the corresponding disulfides by quinolinium fluorochromate (QFC) on silica-gel in excellent yields. Selective oxidation of thiols in the presence of sulfides is also achieved under solid phase conditions. 相似文献
22.
A novel, one-pot reductive mono-alkylation method of amines (primary and secondary), 1,2-phenylenediamine, O-trimethylsilylhydroxylamine, and N,N-dimethylhydrazine was developed using LiClO4 (5 mol %) as a source for in situ generation of imine, iminium ion, oxime, and hydrazone, and zirconium borohydride-piperazine complex as reducing agent. This condition is especially useful for situations in which it is not practical to use the amine in excess (as is typically the case under acid-catalyzed conditions) or for acid-sensitive compounds. 相似文献
23.
M. M. Lakouraj M. Tajbakhsh V. Khojasteh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1865-1870
Mild and efficient method for deprotection of silyl ethers to alcohols is described using Caro's acid supported on silica gel. Reactions are carried out in dichloromethane at room temperature and their parent hydroxy compounds obtained in good to excellent yields. Using this procedure, tetrahydropyranyl ethers (THP) remain intact during desilylation reaction. 相似文献
24.
G. Etherington A. J. Leadbetter X. J. Wang G. W. Gray A. Tajbakhsh 《Liquid crystals》2013,40(3):209-214
Abstract The so-called ‘smectic’ D phase of 4′-n-octadecyloxy-3′-cyanobiphenyl-4-carboxylic acid (one of only four materials known to exhibit this phase) has been shown unambiguously by X-ray diffraction to be characterized by a primitive cubic space group. The space group is either P23 or Pm3, and the lattice parameter a 0 is 86 Å. It is shown that data from previous studies of this phase may be re-intepreted to be consistent with these findings. In view of these conclusions it is clearly inappropriate to refer to the phase as smectic. 相似文献
25.
Majid M. Heravi Dariush Ajami Mahmood Tajbakhsh Mitra Ghassemzadeh 《Monatshefte für Chemie / Chemical Monthly》2000,1(2):1109-1113
A convenient method for the direct conversion of oximes to carbonyl compounds upon treatment with clay supported BTSC under classical heating as well as microwave irradiation in a solvent-free system is described. 相似文献
26.
Mahmood Tajbakhsh Majid M. Heravi Farajollah Mohanazadeh Siavosh Sarabi Mitra Ghassemzadeh 《Monatshefte für Chemie / Chemical Monthly》2001,132(10):1229-1231
Summary. N-Methylpiperidinium chlorochromate adsorbed on alumina was found to be an efficient and selective reagent for the mild oxidative
cleavage of oximes.
Received March 1, 2001. Accepted March 22, 2001 相似文献
27.
Mahmood Tajbakhsh Majid M. Heravi Farajollah Mohanazadeh Siavosh Sarabi Mitra Ghassemzadeh 《Monatshefte für Chemie / Chemical Monthly》2001,45(6):1229-1231
N-Methylpiperidinium chlorochromate adsorbed on alumina was found to be an efficient and selective reagent for the mild oxidative
cleavage of oximes. 相似文献
28.
Fujiwara–Moritani Reaction of Weinreb Amides using a Ruthenium‐Catalyzed C−H Functionalization Reaction 下载免费PDF全文
The ruthenium‐catalyzed Fujiwara–Moritani reaction (oxidative‐Heck reaction) of Weinreb amides is reported herein. The reaction affords exclusively ortho‐C?H olefination products, has excellent substrate scope and tolerates halogen functionalities, which increase the synthetic utility of the method. A variety of activated olefins as well as styrenes can be employed as coupling partners. 相似文献
29.
Yang Z Herd GA Clarke SM Tajbakhsh AR Terentjev EM Huck WT 《Journal of the American Chemical Society》2006,128(4):1074-1075
The confinement of LCE materials into surface monodomains via micropatterning leads to the formation of reversible, shape-shifting surface patterns. The individual features are liquid crystalline monodomains, and by switching to an isotropic state using light or heat, the features switch between imprinted circular features and anisotropic liquid crystalline features. 相似文献
30.
In a recent article, Fadiloglu et al. study an EOQ inventory model with multiple suppliers and binomial yields and conclude that sole sourcing is always optimal. This finding is contrary to the literature advocating diversification of the supply base in the presence of uncertainty. In this note, we present an alternative and more elegant proof of the optimality of sole sourcing in the EOQ model with binomial yield. Our approach extends this result to a general structure for the fixed order cost and provides more insights into the problem. 相似文献