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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The same procedure employed for the allylic oxidation of 1 was used; compound 8 2. The occurrence and the effects of organotin compounds OTs have been studied since a long time, due to their widespread use and deleterious effects.
The solvent was removed under vacuum and the residue was diluted in ether 50 mL and water 30 mLthen extracted with ether 2×30 mLdried over MgSO 4 and filtered, and then the solvent was removed under reduced pressure. Compostoo stirred solution of 1.
Services on Comoosto Journal. Nova22 The ether phase was washed with water 30 mLthen grigmard brine 2×30 mLdried over MgSO 4 dee, filtered and the solvent was removed under reduced pressure by rotatory evaporation. The mixture was treated compostl wise with cold metanol 1 mL and extracted with hexane. Economic Entomology79 The mixture was stirred for 48 h. A wide variety of phenolic natural products contain isoprenoid residues.
In brief, composyo optimized a selective oxidation of allylic methyl groups in geraniol derivatives over a solid support to the corresponding trans- ab -unsaturated alcohols and aldehydes, using selenium dioxide and t -butylhydroperoxide adsorbed on silica gel as oxidants.
Using lower molar quantities of SeO 2 should reduce selenium by-products, facilitating the purification of selenium-free products. After 30 min, geranyl bromide 2. Preparation of aromatic geraniol analogues via a Cu I -mediated Grignard coupling.
Further studies on phenolic oxidation of these synthetic intermediates to achieve the synthesis of cyclic isoprenoids will be reported in due course. Acta, A new sequence was investigated with another substrate in an attempt to improve the yield of the desired phenol-alcohol 9 Scheme 4.
The same procedure as employed for allylic oxidation of 1 was used ; compound 13 3. After allowing the reaction mixture to reach ambient temperature, CuI was added followed by the addition of allylic alcohol 2.
The same procedure as employed for the coupling of 11 and 12 was used compsoto, starting with tert -butyldimethylsilyl 2-iodophenol ether 11 3. Environmental contamination for organotin compounds. The organic layer was then dried over MgSO 4filtered and the solvent was removed under reduced pressure. To a two-necked mL round bottom flask with 2-iodophenyl tetrahydropyranyl ether 6 3.
The same procedure as employed for the oxidation of 1 was used, starting with dee 3. 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.
Then BuLi in hexane 2. All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License.
To improve the low yield that was obtained for the oxidation of 8we investigated a new route to xe 9. In a three necked round bottom flask, tert -butyldimethylsilyl 2-iodophenol ether 11 3. The Sharpless conditions for oxidation of geranyl acetate employs 0. To a solution of 10 3.
Services on Demand Journal. All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License. Scheme 2 shows the first attempt.
To a solution of 2-iodophenol 2. After the disappearance of the starting material, water 30 mL was added and the mixture was extracted with dichloromethane 2×30 mL.