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Magnesium, methoxy

As shown in Scheme 8-11, nucleophilic entry from the a-face (24a) may be hindered by the sterically bulky substituent R2 on the oxazoline moiety therefore entry from the / -face 24/ predominates. Free rotation of the magnesium methoxy bromide may be responsible for the sense of the axial chirality formed in the biaryl product. If the azaenolate intermediate 25 is re-aromatized with a 2 -methoxy substituent complexed to Mg, (iS )-biphenyl product is obtained. Upon re-aromatization of azaenolate 25B, (R)-product is obtained. [Pg.461]

Magnesium, bromo l-(trimethylsilyl)vinyl [49750-22-31,58, 156, 157 Magnesium, methoxy(methyl carbonato-O)- [4861-79-4], 56, 121 Maleic acid, diethyl ester [141-05-9], 58, 80, 82... [Pg.105]

Production of cellulose esters from aromatic acids has not been commercialized because of unfavorable economics. These esters are usually prepared from highly reactive regenerated cellulose, and their physical properties do not differ markedly from cellulose esters prepared from the more readily available aHphatic acids. Benzoate esters have been prepared from regenerated cellulose with benzoyl chloride in pyridine—nitrobenzene (27) or benzene (28). These benzoate esters are soluble in common organic solvents such as acetone or chloroform. Benzoate esters, as well as the nitrochloro-, and methoxy-substituted benzoates, have been prepared from cellulose with the appropriate aromatic acid and chloroacetic anhydride as the impelling agent and magnesium perchlorate as the catalyst (29). [Pg.251]

A-Homo-estra- Q>),2,Aa-triene-4, l-dione (45) from the l-ketal mono-dibromocarbene adduct (43b). A solution of monoadduct 17-ketal (43b 0.46 g) and dry pyridine (20 ml) is heated at reflux for 2 hr. After cooling the reaction mixture, the pyridine hydrobromide (0.1 g) is removed by filtration and the filtrate is concentrated under reduced pressure. The resultant gum is dissolved in ether and washed successively with water, ice-cold 4 N hydrochloric acid, water, 5% aqueous sodium bicarbonate solution, water, saturated salt solution and dried over anhydrous magnesium sulfate. Evaporation of the solvent at reduced pressure gives 3-bromo-4-methoxy-A-homo-estra-2,4,5(10)-trien-17-one (44 0.22 g) mp 158-162° after crystallization from ether. [Pg.371]

Bromo-4-methoxy-A-homo-estra-2,4,5(10)-trien-17-one (44 0. 2g), is dissolved in formic acid, 2 ml of boron trifluoride etherate is added and the mixture is stirred vigorously at 0° for 2 hr. A brown mass ca. 0.12 g) is obtained after evaporation of the solvents at reduced pressure. This material is diluted with water and extracted with chloroform. The chloroform extracts are washed successively with water and saturated salt solution, dried over anhydrous magnesium sulfate and evaporated at reduced pressure to give 95 mg of a product which is purified by filtration through a column of neutral alumina and crystallization of the residue after evaporation of the solvent from ethyl acetate-petroleum ether. The resulting A-homo-estra-l(10),2,4a-triene-4,17-dione (45), mp 143-146°, is identical to the tropone (45) prepared from monoadduct 17-ketone (43a). [Pg.371]

Methoxy-D-Homo-estra-l,3,5(10)-trien-17a-one (96)" (/) Acetic acid (6.4 ml) is added to a stirred solution of estrone methyl ether (93 1.1 g) in ethanol (35 ml) containing potassium cyanide (6 g) at 0°. After being stirred for 1 hr at 0° and 2.5 hr at room temperature, the reactants dissolve and potassium acetate preciptates. Water (65 ml) is added to the reaction mixture and the precipitated solid is collected by filtration. The crude product is dissolved in ethyl acetate and the ethyl acetate solution is washed with water, dried over anhydrous magnesium sulfate and evaporated to dryness under reduced pressure. Recrystallization of a portion of the crude product from cyclohexane-acetone gives 3-methoxy-17a-cyano-estra-l, 3,5(10)-trien-17j5-ol (94a) as needles mp 158.5°. [Pg.388]

Majima et al. prepared ethyl y-(3-indolyl)-y-oxobut3rrate (250) in a similar manner by the condensation of the indole Grignard reagent with -ethoxycarboiiylpropionyl chloride.Methyl y-(3-indolyl)-y-oxobutyrate (251) has been obtained by the action of mcthoxycarbonylpropionyl chloride on indole magnesium iodide in ether. Ballantine et al. prepared methyl y-(5-methoxy-3-... [Pg.77]

Chloro-5,6-diphenyl-as-triazine readily undergoes methoxy-de-chlorination at 25° (< 12 hr) with methanolic methoxide and at 65° (4.5 hr) in non-basified methanol. The chloro group is also displaced by hydrazine (80°, 1 hr), ammonia (140°, 6 hr), and phenyl-magnesium bromide (70°, 12 hr), the latter forming the triphenyl compound 315.3-Chloro-6-phenyl-as-triazine is unstable to cold water or alkali and to hot alcohol or aqueous potassium carbonate. ... [Pg.299]

A solution of 50 grams of N-(a-methylhomoveratryl)-3-methoxy-4-ethoxyphenylacetamide, prepared as set out above, in 200 cc of benzene, is treated with 8 cc of phosphorus oxychloride. The mixture is refluxed for about 3 hours, cooled and then is shaken with a solution composed of 15 grams of sodium hydroxide dissolved in 60 cc of water. The aqueous layer is removed, and the benzene solution is washed with water. The washed benzene solution is dried over anhydrous magnesium sulfate, filtered and evaporated to dryness. The low-melting solid residue is 6,7-dimethoxy-3-methyl-1-(3 -methoxy-4 -ethoxybenzyl)-dihydroisoquinoline base. [Pg.513]

B) t-Butyl 2-Methyl-5-Methoxy-3-lndolylacetate t-Butyl alcohol (25 ml) and fused zinc chloride (0.3 g) are added to the anhydride from Part A. The solution is refluxed for 16 hours and excess alcohol is removed in vacuo. The residue is dissolved in ether, washed several times with saturated bicarbonate, water, and saturated salt solution. After drying over magnesium sulfate, the solution is treated with charcoal, evaporated, and flushed several times with Skellysolve B for complete removal of alcohol. The residual oily ester (18 g, 93%) is used without purification. [Pg.811]

A solution of 18 g of 2-thienyl bromide in 30 ml of tetrahydrofuran Is gradually added to a mixture of 2.6 g of magnesium and 80 ml of tetrahydrofuran under stirring at 50°C. The mixture is stirred for 5 hours at room temperature until the magnesium is entirely dissolved in the solution. 6.2 g of methyl N-methyl-5-methoxy-nipecotinate are added to the mixture. Then, the mixture is refluxed for 4 hours. After the reaction Is completed, tetrahydrofuran is distilled off under reduced pressure. An aqueous ammonium chloride solution is added to the residue, and the solution is extracted with chloroform. The extract is dried and then evaporated to remove chloroform. The viscous oil thus obtained is recrystallired from a mixture of benzene and ether. 7 g of di-(2-thienyl) -(N-methyl-5-methoxy-3-piperidyl)-carbinol are obtained as crystals. Melting point 142°C to 146°C. [Pg.1488]

Cj]HyBrMgO 38046-82-1) see Naproxen (5)-2-(5-bromo-6-methoxy-2-naphthyl)propanoic acid (Ci4Hi BrO 84236-26-0) see Naproxen bromo(3-methoxyphenyl)magnesium (C7H7BrMgO 36282-40-3) see Tramadol (/f)-2-bromo-A -[2-(4-methoxyphenyl)-l-methylethyl]-acetamide... [Pg.2314]

PHENYL-METHOXY)CARBONYL] -L-PROLYL]-GLYCYL]-, ETHYL ESTER [57621-06-41,56,88 Grignard reagent, 3-(dimethylamino)propyl-magnesium chloride, 55, 127 methylmagnesium bromide, 55, 63... [Pg.129]

Acyl imidazolides are more reactive than esters but not as reactive as acyl halides. Entry 7 is an example of formation of a (3-ketoesters by reaction of magnesium enolate monoalkyl malonate ester by an imidazolide. Acyl imidazolides also are used for acylation of ester enolates and nitromethane anion, as illustrated by Entries 8, 9, and 10. (V-Methoxy-lV-methylamides are also useful for acylation of ester enolates. [Pg.154]

Figure 24 Comparison of isothermal chemiluminescence intensity for pullulan (1) and pullulan impregnated by methoxy magnesium methyl carbonate (2) from a 5% solution in methanol initial molar mass of pullulan 404 kg/mol, oxygen atmosphere, temperature 190°C. Figure 24 Comparison of isothermal chemiluminescence intensity for pullulan (1) and pullulan impregnated by methoxy magnesium methyl carbonate (2) from a 5% solution in methanol initial molar mass of pullulan 404 kg/mol, oxygen atmosphere, temperature 190°C.
The starting bibenzyl was prepared from -methoxybenzyl chloride by a modified Wurtz reaction. The checkers found the procedure described by Buu-HoY and Lavit inadequate and used the copper(I) chloride-catalyzed coupling of -methoxy-phenyl magnesium chloride in its place. [Pg.28]

Direct preparation of azo compounds in good yields is accomplished by treatment of nitro compounds with lithium aluminum hydride [576], with magnesium aluminum hydride [577], with sodium bis(2-methoxy ethoxy)aluminum hydride [575], with silicon in alcoholic alkali [331] or with zinc in strongly alkaline medium [578], Hydrazobenzene was obtained by controlled hydrogenation of nitrobenzene in alkaline medium (yield 80%) [572] and by reduction with sodium bis 2-methoxyethoxy)alumium hydride (yield 37%) [544],... [Pg.72]

High yields of amines have also been obtained by reduction of amides with an excess of magnesium aluminum hydride (yield 100%) [577], with lithium trimethoxyaluminohydride at 25° (yield 83%) [94] with sodium bis(2-methoxy-ethoxy)aluminum hydride at 80° (yield 84.5%) [544], with alane in tetra-hydrofuran at 0-25° (isolated yields 46-93%) [994, 1117], with sodium boro-hydride and triethoxyoxonium fluoroborates at room temperature (yields 81-94%) [1121], with sodium borohydride in the presence of acetic or trifluoroacetic acid on refluxing (yields 20-92.5%) [1118], with borane in tetrahydrofuran on refluxing (isolated yields 79-84%) [1119], with borane-dimethyl sulflde complex (5 mol) in tetrahydrofuran on refluxing (isolated yields 37-89%) [1064], and by electrolysis in dilute sulfuric acid at 5° using a lead cathode (yields 63-76%) [1120]. [Pg.167]


See other pages where Magnesium, methoxy is mentioned: [Pg.121]    [Pg.135]    [Pg.412]    [Pg.141]    [Pg.121]    [Pg.135]    [Pg.412]    [Pg.141]    [Pg.498]    [Pg.437]    [Pg.83]    [Pg.108]    [Pg.382]    [Pg.377]    [Pg.254]    [Pg.811]    [Pg.865]    [Pg.262]    [Pg.103]    [Pg.103]    [Pg.186]    [Pg.190]    [Pg.809]    [Pg.490]    [Pg.144]    [Pg.81]    [Pg.259]    [Pg.100]    [Pg.1001]    [Pg.95]    [Pg.104]    [Pg.1122]    [Pg.73]    [Pg.36]   
See also in sourсe #XX -- [ Pg.4 , Pg.121 ]




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