反应详情

To a stirred suspension of samarium metal (758 mg, 5.0 mmol) and 3 Å molecular sieves (0.5 g) in anhydrous tetrahydrofuran (THF, 9.5 mL) was slowly added a solution of 1,2-diiodoethane (1.3 g, 4.6 mmol) in THF (9.5 mL) at ambient temperature. After the reaction stirred for 30 min, hexamethylphosphoramide (HPMA, 3.0 mL, 17.2 mmol) was added to the reaction mixture and continued stirring for an additional 20 min. Then, a solution of ketone 1 (500.0 mg, 1.16 mmol) in THF (6.0 mL) was added followed by a solution of 1-bromo-5-methylhexane (208.0 mg, 1.16 mmol) in THF (2.0 mL). The reaction was allowed to stir for an additional hour until the starting material was completely consumed. After this, the reaction mixture was slowly treated with saturated NaHCO3, filtered through Celite and rinsed three times with an excess amount of diethyl ether. The filtrate was treated with water and extracted with diethyl ether. The ether extracts were washed with brine, dried over Na2SO4 and evaporated in vacuo to give a residue which was purified via silica gel chromatography. Elution with hexane-diethyl ether (4:1, v/v) afforded compound 2 (350.0 mg, 0.6 mmol, 57%) as a white powder (Honda et al. (1996) J. Chem. Soc., Perkin Trans. 1, 2291-2296).

1. stirringcontinued stirring for an additional 20 min
2. stirringto stir for an additional hour until the starting material
3. customwas completely consumed
4. additionAfter this, the reaction mixture was slowly treated with saturated NaHCO3
5. filtrationfiltered through Celite
6. washrinsed three times with an excess amount of diethyl ether
7. additionThe filtrate was treated with water
8. extractionextracted with diethyl ether
9. washThe ether extracts were washed with brine
10. dry with materialdried over Na2SO4
11. customevaporated in vacuo
12. customto give a residue which
13. customwas purified via silica gel chromatography
14. washElution with hexane-diethyl ether (4:1