反应详情

A solution (0.5 M) of butenyl magnesium bromide in THF (1.4 eq) was treated at −78° C. with Cu(I)Br.SMe2 (0.05 eq) and HMPA (2.4 eq). The mixture was stirred for 10 min, then a solution (1 M) of acrolein (1 eq) and TMSCl (2 eq) in THF was added over 1 h such that the internal temperature remained below −68° C. The resulting mixture was stirred at −78° C. for 2 h, then treated with excess Et3N and diluted with hexane. After reaching room temperature, the mixture was treated with a small portion of H2O and filtered through CELITE. The filtrate was washed 10 times with H2O and then with brine. The organic layer was dried, and the volatiles were removed to give a residue that was distilled under reduced pressure (20 mbar). The fraction collected at 80-86° C. contained the title compound (58%) as a colorless liquid. 1H NMR (400 MHz, CDCl3) δ 6.19 (d, J=11.6 Hz, 1H), 5.85-5.75 (m, 1H), 5.02-4.92 (m, 3H), 2.08-2.02 (m, 2H), 1.94-1.88 (m, 2H), 1.46-1.38 (m, 2H), 0.18 (s, 9H).

1. customremained below −68° C
2. stirringThe resulting mixture was stirred at −78° C. for 2 h
3. customAfter reaching room temperature
4. filtrationfiltered through CELITE
5. washThe filtrate was washed 10 times with H2O
6. customThe organic layer was dried
7. customthe volatiles were removed
8. customto give a residue that
9. distillationwas distilled under reduced pressure (20 mbar)
10. customThe fraction collected at 80-86° C.