Isobutyl Sulfonate

The isobutyl sulfonate was examined as a replacement for the isopropyl sulfonate, which had undesirable stability properties. Cleavage occurs with 2 eq. of Bu4N I and proceeds much more readily than cleavage of the isopropyl sulfonate. ... 

Isobutyl Sulfonate. With Silver(I) p-Tobienesulfonate, alkyl chloroformate forms sulfonic carbonic anhydride which when heated liberates carbon dioxide, producing alkyl sulfonate. In order to find out the mechanism of the decomposition of the mixed anhydride, reaction of isobutyl chloroformate and silver p-toluenesulfonate was investigated. If the free alkyl cation, i.e. isobutyl carbonium ion, is formed, the rearrangement to i-butyl and r-butyl carbonium ion would be expected, finally resulting in the formation of j-butyl p-toluenesulfonate. r-Butyl p-toluenesulfonate is unstable and is not expected to survive under the reaction conditions. In fact, decomposition gave a mixture of isobutyl p-toluenesulfonate and J-butyl />-toluenesulfonate in a 0.8 1 mol ratio, with a quantity of isobutene and free p-... 

To this mixture there is then added slowly over a period of 30 minutes 10 grams of - -)-a-aminobenzylpenicillin beta-naphthalene sulfonate. The mixture is agitated for 3 hours at 25°-30°C. The product, D- -)-o -aminobenzylpenicillin trihydrate precipitates and is collected by filtration. The filter cake of the product is washed several times with methyl isobutyl ketone and is dried at 40°C. The product is obtained in about a 90% yield and has a potency of 865 mcg/mg. It is determined by Karl Fischer analysis to have a moisture content of 13.4% by weight. 

B-Bromocatecholborane, 47 Bromodimethylborane, 47 B-Chlorocatecholborane, 47 Chlorotriisopropoxytitanium, 213, 226 Copper(II) bromide, 112 Dialkylboryl trifluoromethane-sulfonates, 340 Dichlorobis( 1 -phenylethoxy)-titanium(IV), 12 Dichlorobis(trifluoromethane-sulfonato)titanium(IV), 102 Dichlorodiisopropoxytitanium(I V), 12 Diethylaluminum chloride, 173 Diethylaluminum fluoride, 25 Dimethylaluminum chloride, 5 Ethylaluminum dichloride, 5, 44, 306 Ferric chloride, 133 Ferric chloride-Silica, 134 Isobutyl(2,4,6-tributylphenoxy)-aluminum trifluoromethanesulfonate, 113... 

Unless otherwise noted, acetone was the solvent. b Yield of deoxyiodo-sugar derivative. 0 Yield of sodium sulfonate. Yield by determination of sodium iodide consumed. Free iodine liberated. / Acetonylacetone. Corrected for solubility of sodium sulfonate in acetone. A Acetic anhydride. Isobutyl methyl ketone. 

TRS 10-410/IBA. Solutions containing 5.0% by weight TRS 10-410 surfactant (Witco) and 3.0% reagent grade isobutyl alcohol (IBA) were used in the salinity range of 0.7 to 2.3 gm/dl. The surfactant is a 61.5% - active mixture of petroleum sulfonates with an equivalent weight of 424. 

Phase Behavior of Aqueous Surfactant Solutions. The aqueous solu-tions contained 5 gm/dl TRS l0-4l0 as surfactant, and 3 gm/dl isobutyl alcohol as cosurfactant, unless otherwise indicated. The polymer concentration was varied from zero to 1500 ppm. The aqueous phase behavior in the absence of polymer is shown in Figure 2. The salinity is varied from 0.8 to 2.2 gm/dl NaCl in increments of 0.2 gm/dl. The phase behavior at lower salinities will be discussed later. The general trend is similar to the changes in textures reported for other commercial and model sulfonate solutions (26,27). 

Alkyl-bridged ions may be generated as potential intermediates in 1,2-alkyl shifts ( a route ), by double bond participation ( tt route ), and by protonation of cyclopropanes. In the acylic series, kinetic methods are not very useful for detecting alkyl participation. The solvolyses of alkyl sulfonates proceed with 1,2-alkyl shifts only in the case of neopentyl-type substrates, (612) and (613). Isobutyl (610) and 3-methyl-2-butyl sulfonates (611) prefer solvolytic displacement and 1,2-H shifts. Alkyl shifts in (610) and (611) are induced only by deamination (X=Nj) and related reactions which are not amenable to kinetic studies. 

Considering the selectivity of this reaction (terminal vs. 1,2-disubstituted alkenes) and the fact that an electron-rich alkene such as isobutyl vinyl ether does not undergo cyclopropanation, it seems that the reactive species formed from the lithiated sulfone and the nickel catalyst does not behave as an electrophilic carbenoid. In this respect, one should note that the Simmons-Smith reagent is electrophilic whereas the methylene transfer reagent arising from treatment of dibromomethane with nickel(O) can achieve cyclopropanation of electron-deficient alkenes only. ... 

Novel sulfonated and carboxylated ionomers having "blocky" structures were synthesized via two completely different methods. Sulfonated ionomers were prepared by a fairly complex emulsion copolymerization of n-butyl acrylate and sulfonated styrene (Na or K salt) using a water soluble initiator system. Carboxylated ionomers were obtained by the hydrolysis of styrene-isobutyl-methacrylate block copolymers which have been produced by carefully controlled living anionic polymerization. Characterization of these materials showed the formation of novel ionomeric structures with dramatic improvements in the modulus-temperature behavior and also, in some cases, the stress-strain properties. However no change was observed in the glass transition temperature (DSC) of the ionomers when compared with their non-ionic counterparts, which is a strong indication of the formation of blocky structures. 

Peptide synthesis. Izumiya and Muraoka1 examined the extent of isomerization with commonly used coupling reagents (isobutyl chloroformate, DCC, N-ethyl-5-phenylisoxazolium-3 -sulfonate, and EEDQ) and of these found that EEDQ caused the least racemization (0.2%) in the particular test chosen. The next most satisfactory was N-ethyl-5-phenylisoxazolium-3 -sulfonate (Woodward s Reagent K, 1.7-1.8%). 

A new radical allylation procedure has been applied to the synthesis of a 3 -C-allyl-2, 3 -dideoxypyrimidine nucleoside, and lactone 121, made by photochemical addition of isopropanol to the corresponding 2,3-ene, has been converted to the nucleoside 122. Branched-chain sulfonates 123 have been made from 3 -ketonucleosides, and the isobutyl group was found to be superior to other possibilities, it being cleavable by iodide ion to give the sulfonic acid, an analogue of a 3 -phosphate. An ingenious route to related phosphonates is outlined in... 

As host polymer matrices we used poly(alkyl methacrylate)s with various ester groups (methyl PMMA, ethyl PEMA, isopropyl PiPMA, normalpropyl PnPMA, isobutyl PiBMi normjdbutyl PnBMA), poly(methyl acrylate), polyethylene (PE), poly(vinyl chloride) (PVQ, poly(vinylidene chloride) (PVDQ, j lyfvinyl alcohol) (PVOH), polystyrene (PS), polycarbonate (PQ, phenolphthalein polyedier-ketone (PEK-Q, and phenolphthalein polyether-sulfone (PES-C). 

Vinyl isobutyl ether Vinylmethyidichlorosilane Vinylmethyidiethoxysilane Vinyltoluene monomer Vinyltriacetoxy silane Vinyltriethoxysilane Vinyltris (trimethylsiloxy) silane Xylene sulfonic acid Zinc nitrate Zinc sulfate monohydrate Zinc undecylenate intermediate base Butyronitrile intermediate fibers Nitroethane intermediate industry... 

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