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Tertiary butoxide

Preparation of nefopam starts with the acylation of aminobenzhydrol 1 (obtainable by reduction of the corresponding benzoylbenzamide) with chloroacetyl chloride treatment of the chloroamide (2) with potassium tertiary butoxide results in internal alkylation to give the eight-membered ring (3). Reduction of the lactam function with lithium aluminum hydride gives the amine and, thus, nefopam (4). ... [Pg.447]

Several dehydrohalogenation reactions have been carried out with the help of DMSO. Thus isopropyl bromide has been successfully converted to propene by heating with potassium tertiary butoxide-DMSO mixture at 550°. [Pg.311]

Solvent-extracted delignified beech wood pulp was treated with potassium tertiary butoxide, then with quinone methides at 25 °C or 45 °C (Figure 4.13). Following reaction, extensive solvent extraction was then performed, and the modified flour was pressed to form a disc, which was then exposed to C. versicolor or G. trabeum. No indication of biological attack was found (Loubinoux etal., 1992). [Pg.97]

Recent Developments in the Chemistry of Fluorinated Isopropoxides and Tertiary Butoxides ... [Pg.468]

In their reactions with tertiary butylhydroperoxide, H and eaq show a different selectivity (Phulkar et al. 1990). While H undergoes reactions (12) and (13) with about equal probability, i.e both fBuO and OH are formed, eaq yields only fBu() [reaction (14)]. This preference in splitting the peroxidic bond is due to the much higher solvation energy of the hydroxide compared to the tertiary butoxide ion. For a detailed study on the reaction of H with H202 see Mezyk and Bartels (1995). [Pg.81]

To 100 g of 2-(N-methyl-N-(2-pyridyl)amino)ethanol in 500 ml DMF was added 100 g of 4-fluorobenzaldehyde. The reaction mixture was stirred for 10 min at room temperature and 80 g of potassium tertiary butoxide was added to the reaction mixture. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was cooled to 5-10°C and under the cold conditions, 1.5 L of water was added and stirred for 15 min. The mixture was extracted with ethyl acetate. The combined organic layer was washed with 3 times 1 L water. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure to give 148 g (88%) of 4-[2-(N-methyl-N-(2-pyridyl)amino)ethoxy)benzaldehyde. [Pg.3005]

Chapter VII.3). The conversion of VII/31to VII/32 (Scheme VII/8) however, goes in very good yield. Compound VII/33 is formed by transesterification [17]. One, two, and three carbon atom expansions, following the same reaction principle, have been published quite recently [19] [19a], By this method, ethyl l-methoxycarbonylmethyl-2-oxocyclohexancarboxylate, for example, can be transformed to ethyl 2-methoxycarbonyl-3-oxocycloheptancarboxylate in the presence of 1.2 equivalents of potassium tertiary butoxide in dimethylsulfoxide (41% yield). [Pg.132]

Etherified units. Consistent with the generally accepted mechanism (D, Fig. 14), the erythro dimer of etherified P-aryl ether was about four times more reactive than the threo isomer [350]. The ether cleavage, besides being enhanced by increasing alkalinity, was facilitated in the presence of monoetha-nolamine [351] or in a DMSO-potassium-tertiary butoxide solution [330]. [Pg.76]

Polymers with different end groups usually also have differences in thermal stability. It has been found that tertiary amines or quaternary ammonium salts initiated chloral polymers have very poor thermal stability. Triphenyl phosphine initiated polychloral samples have good thermal stability and the lithium tertiary butoxide initiated polychloral has a thermal stability close to that of the phosphine initiated polymers. [Pg.375]

The reaction of CAN with NaO-r-Bu can be utilized (64) for the preparation of binary as well as sodium ceric tertiary butoxides. [Pg.251]

As early as 1959, Bradley and Factor (583) suggested the use of zirconium tertiary butoxide [Zr(0-r-Bu)4, bp, —50°C/1 mm1] as a suitable precursor. This use is based on its decomposition to ZrOz at around 200-250°C through a chain reaction involving the hydrolysis of the alkoxide by water, formed in a... [Pg.424]

There are, however, other examples. In the presence of potassium tertiary butoxide, quinine and benzophenone are equilibrated with quininone and benzhydrol.37 Benzyl,38 methyl,39 ethyl,39 40 propyl,39 butyl,39 and amyl39 alcohols will reduce ketones to the corresponding secondary alcohols on heating at high temperatures with sodium or potassium hydroxide. In all these cases it is probable that the reaction proceeds by the intermolecular transfer of a hydride ion from the alkoxide ion to the carbonyl group. [Pg.170]

Four precipitated iron-based catalysts were used. The first catalyst consisted of only iron. The other catalysts contained either added potassium, added silicon or both. The catalysts were designated in terms of the atomic ratios as lOOFe, 100Fe/3.6Si, 100Fe/0.71K and 100Fe/3.6Si/0.71K. The catalysts were prepared by continuous precipitation from iron (111) nitrate and concentrated ammonium hydroxide. For silica-containing catalysts, a colloidal suspension of tetraethyl ortho silicate was mixed with the iron nitrate solution prior to precipitation. Potassium was added to the catalysts in the form of potassium tertiary butoxide during the loading of the FTS reactor. [Pg.528]

The enol ether of dihydrocodeinone, dihydrothebaine, can be prepared by the action of methyl sulphate and potassium tertiary butoxide on the ketone [72]. [Pg.176]

The structural problem remains unsolved, but as dihydrocodeinones can be converted into dihydrothebaines by sodium tertiary butoxide and methyl sulphate, it is possible that the problem will receive a solution by the degradation of methyl- and isomethyldihydrothebaines in a manner similar to the degradation of dihydrothebaine to [xvii] or [xvm] [13-14] (see Chap. XIII). [Pg.266]

Liriodenine can also be prepared by oxidation of the aporphine unshinsunine (Id) 14 16) or roemerine (le) with chromium trioxide in pyridine 14). Other oxidizing agents which afford hriodenine from ushinsunine are acidic potassium permanganate, selenium dioxide, and selenium 15). A superior method involves the air oxidation of a potassium tertiary butoxide in i-butyl alcohol solution of anonaine (If) 17). [Pg.227]

Compound 110, readily prepared from 111 and acrylic acid at 135°, underwent the same sequence of reactions used in the model series, yielding exclusively 112 in which it is inferred that the hydrogen at C-4 is trans to the bridging group. The ketone was converted into the alcohol 113 and thence to the mesylate 114 which in turn was transformed to the alkene 115 with potassium tertiary butoxide in DMSO. Only under these conditions was 115 obtained in high yield uncontaminated with rearranged products. Functionality at C-5 was introduced by oxidation with selenium dioxide in glacial acetic acid. Acetate 116 so obtained was hydrolysed to the alcohol 117 and oxidized to the racemic ketone 118. One of the enantiomers of 118 had already been prepared from annotinine (1) and comparison of the spectroscopic properties of 118 with the naturally derived sample established the identity of the two systems. [Pg.381]

The hydrolysis of tertiary butoxide zirconium (0.5 mole water/mole of alkoxide) at 60°C and finally at 110°C gave a product (78) of composition (Bu0)6Zr20 as a semisolid crystalline mass. An increased proportion of water gave solids of composition (Bu0)sZr302, (BuO)ioZr403, and (BuO)32ZrioOg. [Pg.61]

Ball and stick model of potassium tertiary-butoxide. B... [Pg.210]

Cholesteryl acetate dibromide is first prepared by the acetylation of chloesterol and its subsequent bromination. This on oxidation with chromium-6-oxide reduces the 8-carbon side chain at C-17 to a mere CO moiety, which on reduction followed by hydrolysis yields dehydroepiandro-sterone. The resulting product on acetylation protects the acetyl moiety at C-3 and treatment with sodium propoxide introduces a hydroxy group at C-17. Benzoylation followed by mild hydrolysis causes the reappearances of free OH moiety at C-3 and a benzoxy function at C-17. Oppeanauer oxidation cuased by refluxing the resulting secondary alcohol with aluminium tertiary butoxide in excess of acetone affords a ketonic function at C-3, which upon hydrolysis in an alkaline medium yields the official compound. [Pg.693]

A valuable method for converting one alkoxide to another is an ester exchange reaction [20], This method is particularly suited for the preparation of the tertiary butoxide from the isopropoxide and r-butyl acetate. The reaction is as follows ... [Pg.77]

Mazdiyasni [22,23] reported the direct pyrolysis of the metal alkoxides, which form very fine ceramic powders. The overall thermal decomposition of a liquid zirconium tertiary butoxide to Zr02 is as follows ... [Pg.77]

Bases. NaOC2Hg (Sodium Ethoxide) HN (C2Hg)2 (Diethylamine) KOH (Potassium Hydroxide) KOC (CHg)3 (Potassium tertiary-Butoxide) N (C2Hg)g (Triethylamine) NaH (Sodium Hydride). [Pg.192]

Finally, mention may be made of the high susceptibility of the alkali enolates to attack by oxygen (96). In the presence of potassium tertiary butoxide, quininone reacts smoothly with one mole of oxygen, to give potassium quininate, and the tertiary butyl ester of meroquinene. The reaction very probably involves the formation of an unstable cyclic peroxide (LXXII), which decomposes as shown to the salt of quininic... [Pg.16]


See other pages where Tertiary butoxide is mentioned: [Pg.338]    [Pg.331]    [Pg.427]    [Pg.357]    [Pg.837]    [Pg.928]    [Pg.580]    [Pg.1286]    [Pg.34]    [Pg.57]    [Pg.186]    [Pg.181]    [Pg.420]    [Pg.426]    [Pg.172]    [Pg.204]    [Pg.406]    [Pg.390]    [Pg.210]    [Pg.77]    [Pg.2767]    [Pg.5453]    [Pg.15]   
See also in sourсe #XX -- [ Pg.77 ]




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