Dibenzyl-ethyl

Et glycoside, 4,6-dibenzyl Ethyl 4,6-di-O-benzyl-2,3-dideoxy-a-D-erythro-hex-2-enopyranoside C22H26O4 354.445 Md +91 (c, 1.2 in CHCI3). 

The dibenzyl ketone has a very high b.p. (ca. 200°/21 mm.) and this remains in the flask when the unsymmetrical ketone has been removed by distillation. The dialkyl ketone has a comparatively low b.p. and is therefore easily removed by fractionation under normal pressure acetone is most simply separated by washing with water. In this way methyl benzyl ketone (R = CHj), ethyl benzyl ketone (R = CHgCH,) and n-propyl benzyl ketone (R = CHjCHjCH,) are prepared. By using hydrocinnamic acid in place of phenylacetic acid ... 

The methylation of N-methyl derivatives of maleic hydrazide gives in general O-alkylated products. The opposite results are obtained with benzyl halides as alkylating agents. In this case the O-benzyl derivative (71) is formed, which is then further benzylated to the lV,0-dibenzyl derivative (72). When ethyl chloroacetate is used, the direction of alkylation is dependent on pH. At pH above 8, O-alkylation occurs at pH below 8, N-alkylation takes place exclusively in neutral and acidic solutions only IV-alkylated products are formed. 

Peroxides. These are formed by aerial oxidation or by autoxidation of a wide range of organic compounds, including diethyl ether, allyl ethyl ether, allyl phenyl ether, dibenzyl ether, benzyl butyl ether, n-butyl ether, iso-butyl ether, r-butyl ether, dioxane, tetrahydrofuran, olefins, and aromatic and saturated aliphatic hydrocarbons. They accumulate during distillation and can detonate violently on evaporation or distillation when their concentration becomes high. If peroxides are likely to be present materials should be tested for peroxides before distillation (for tests see entry under "Ethers", in Chapter 2). Also, distillation should be discontinued when at least one quarter of the residue is left in the distilling flask. 

Comparison of Table 5.4 and 5.7 allows the prediction that aromatic oils will be plasticisers for natural rubber, that dibutyl phthalate will plasticise poly(methyl methacrylate), that tritolyl phosphate will plasticise nitrile rubbers, that dibenzyl ether will plasticise poly(vinylidene chloride) and that dimethyl phthalate will plasticise cellulose diacetate. These predictions are found to be correct. What is not predictable is that camphor should be an effective plasticiser for cellulose nitrate. It would seem that this crystalline material, which has to be dispersed into the polymer with the aid of liquids such as ethyl alcohol, is only compatible with the polymer because of some specific interaction between the carbonyl group present in the camphor with some group in the cellulose nitrate. 

Cyclopropyl-3-fluoro-2-hydroxy-6-oxo-6//-pyrido[l,2-n]pyrimidine-7-carboxylates 340 were obtained in the reaction of 2-cyclopropyl-2-(5-fluoro-4-hydroxy-2-pyrimidinyl)acetaldehyde (339) and ethyl, rerr-butyl and dibenzyl malonates in the presence of piperidine and AcOH (95MIP1, 96JMC3070, 96MIP4, 96USP5580872). 

Condensation of 2-azido benzonitrile derivatives 703 with ethyl aeetonediearboxylate in presenee of NaOEt gave the triazoloquinoline derivatives 705 presumably through the intermediate 704 (90S654). Reaetion of 703 with dibenzyl ketone gave the triazole 706 aeeompanied by 707 whieh upon treatment with NaH in THF afforded 706 (97S773) (Seheme 122). 

Bohme77 employed excess monoperphthalic acid in diethyl ether to oxidize dibenzyl and benzyl ethyl sulphoxides. Reaction time was 24 h at - 15 to + 10 °C, after which he added potassium iodide and water and titrated the iodine set free with thiosulphate. Dickenson78 oxidized dimethyl sulphoxide in malt, wort or beer with Na2S2Os. In... 

L-phenylalanyl L-phenylalanine methyl ester L-prolyl L-alanine methyl ester L-prolyl L-aspartic dibenzyl ester L-prolyl glycine ethyl ester L-prolyl methyl ester L-serylglycine ethyl ester... 

Kugelrohr-Destillation des Riickstandes (0,13 g) bei 160-200° (Block-Temperatur)/0,005 Torr (0,67 Pa) und anschlieBende preparative Diinnschicht-Chromatographie an Aluminiumoxid (Chlorofonn/Ethyl-ace-tat) ergibt als erstes groBes Band 1. -Dibenzyl-2.31 -bipyrrolidinyl Ausbeute 60 mg (Ol). 

The chemistry of radical sites adjacent to phosphatoxy centers elicited interest because of the involvement of such species in DNA degradation processes. These species can give rise to rearrangement, elimination, and substitution products, and for some time concerted eliminations and migrations as well as heterolysis to a radical cation and a phosphate anion were considered to be involved (Scheme 2). Recently, experimental studies of the l,2-dibenzyl-2-(diphenylphosphatoxy)-2-phenylethyl radical and complementary theoretical studies of l,l-dimethyl-2-(dimethylphosphatoxy)ethyl radical have been interpreted as indicating that a radical cation/anion pathway with initial formation of 49 is favored. ... 

Problem 14.55 Prepare the following ethers starting with benzene, toluene, phenol (C H OH), cyclohexanol, any aliphatic compound of three C s or less and any solvent or inorganic reagent a) dibenzyl ether, b) di-/i-butyl ether, (c) ethyl isopropyl ether, d) cyclohexyl methyl ether, (e) p-nitrophenyl ethyl ether, (/) divinyl ether (g) diphenyl ether. <... 

Problem 15.47 Give another acceptable name for each of the following (a) dimethyl ketone, (b) l-phenyl-2-butanone, (c) ethyl isopropyl ketone, (d) dibenzyl ketone, (e) vinyl ethyl ketone. ... 

Dibenzyl sulphide [528-74-9] M 214.3, m 48.5 . Crystd from EtOH/water (10 1), or repeatedly from purified hot ethyl ether. Vacuum dried at 30 over P2O5, fused under nitrogen and re-dried. 

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