COMPOSTO DE GRIGNARD PDF
5 jul. 1- Dados os compostos de Grignard abaixo, forneça a nomenclatura de cada um deles: a) H3C — CH2— CH2— CH2— MgCl Cloreto de butil-. Keywords: allylic oxidation, selenium dioxide, homoallylic alcohols, Grignard adsorvido em SiO2, propicia uma rota conveniente para tais compostos. O primeiro estudo sistemático sobre os compostos organoestânicos (OTs, .. tetrassubstituído via reação de “Grignard” (brometo ou cloreto de etil, butil ou.
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Using lower molar quantities of SeO 2 should reduce selenium by-products, facilitating the purification of selenium-free products. The ether phase dde washed with water 30 grigmardthen with brine 2×30 mLdried over MgSO 4filtered and the solvent was removed under reduced pressure by rotatory evaporation.
C -geranyl and C -farnesyl phenols have been prepared by reaction of geranyl or farnesyl bromide with the sodium salt of the phenol. To a solution of 2-iodophenol 2.
Environmental contamination for organotin compounds. The reaction was cooled, a saturated solution of NH 4 Cl was added, the solutions was extracted with ether 3×50 mLdried over MgSO 4filtered and the solvent was removed under reduced pressure by rotatory evaporation. Emo consumo de OTs era estimado em cerca de toneladas por ano 3. The occurrence and grigbard effects of organotin compounds OTs have been studied since a long time, due to their widespread use and deleterious effects.
To improve the low yield that was obtained for the oxidation of 8we investigated a new route to reach 9. Economic Entomology79 In a three necked round bottom flask, tert -butyldimethylsilyl 2-iodophenol ether 11 3. Results and Discussion The Sharpless conditions for oxidation of geranyl acetate employs 0. After 30 min, geranyl bromide 2. The organic layer was washed with two portions of brine then dried with anhydrous MgSO 4. To a two-necked mL round bottom flask with 2-iodophenyl tetrahydropyranyl ether 6 3.
New York,vol. The same procedure as employed for the oxidation of 1 was used, starting with 7 3.
Services on Demand Journal. Further studies on phenolic oxidation of these synthetic intermediates to achieve the synthesis of cyclic isoprenoids will be reported in due course. The same procedure employed for the allylic oxidation of 1 was used; compound 8 2. Geraniol was purchased from Aldrich Chem. Tetrahydro-2 H pyranyl ether 7 3.
The mixture was stirred at ambient temperature for 8 h and then diluted with 30 mL of ether. How to cite this article. New York,p. The chosen protecting groups clearly influence the oxidation process. A new sequence was investigated with another substrate in an attempt composyo improve the yield of the desired phenol-alcohol 9 Scheme 4. Compostl same procedure as employed for allylic oxidation of 1 was used ; compound 13 3.
To a solution of 10 3. Comosto the disappearance of the starting material, water 30 mL was added and the mixture was extracted with dichloromethane 2×30 mL.
Nova22 The same procedure as employed for the coupling of 11 and 12 was usedstarting with tert -butyldimethylsilyl 2-iodophenol ether 11 3. Kascheres on occasion of his 60 th birthday. Conclusion In brief, we optimized a selective oxidation of allylic methyl groups in geraniol derivatives over a solid support to the corresponding trans- ab -unsaturated alcohols grignatd aldehydes, using selenium comlosto and t -butylhydroperoxide adsorbed on silica gel as oxidants.
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Also, we developed an efficient synthesis of 2-geranylphenol derivatives via a Cu I -mediated Grignard coupling of 2-lithiophenols and geranyl substrates. A solution of 2. Some OTs are used as pesticides in crops, or as biocides in antifouling paints, applied in the ship hulls to avoid attachment and growth of tube worms, mussels and barnacles.
The extracts were washed with a saturated aqueous solution of FeSO 4. Also, an efficient synthesis of 2-geranylphenol derivatives via d Cu I -mediated Grignard coupling of 2-lithiophenols and geranyl substrates was developed.
Em Organotin Compounds ; Sawyer, A. Preparation of aromatic geraniol analogues via a Cu I -mediated Grignard coupling. The mixture was stirred for 48 h.
Preparation of aromatic geraniol analogues via a Cu(I)-mediated Grignard coupling
Geranyl bromide 4 was necessary in the next steps and its preparation although it is commercially available was achieved after some attempts in order to optimize the conditions for getting high yield.
Preparative column chromatography was carried using silica gel 60 Merckmesh. A wide variety of phenolic natural products contain isoprenoid residues. The mixture was treated drop wise with cold metanol 1 mL and extracted with hexane.