Ammonium Chloride → 2-[3-(4-Allyldimethylsilylphenyl)propoxy]tetrahydro-2H-pyran

Temperature

-78 °C

To a solution of 1-allyldimethylsilyl-4-bromobenzene (1 Scheme 1, 1.3 g, 5 mmol) in dry THF (10 mL) at −78° C. was added t-butyllithium (3.0 mL, 1.7 M solution in pentane, 5.1 mmol) over a period of 5 min. After 30 min stirring at −78° C., 2-(3-bromopropoxy)tetrahydro-2H-pyran (850 μL, 5 mmol) was added dropwise. The reaction mixture was warmed to room temperature and stirred further for 16 h. Concentrated NH4Cl (1 mL) was added to the solution, and the reaction mixture was concentrated under reduced pressure. The residue was extracted with ethyl acetate (10 mL) and brine (5 mL), and the organic layer was dried (Na2SO4), concentrated. The crude product was purified by column chromatography (1:20 ethyl acetate/hexanes) to afford a colorless oil (621 mg, 39%). 1H NMR (300 MHz, CDCl3) δ 0.33 (s, 6 H), 1.52-1.94 (8H), 1.99 (m, 2 H), 2.77 (m, 2 H), 3.40-3.57 (m, 2 H), 3.78-3.96 (m, 2 H), 4.64 (m, 1 H), 4.88 (s, 1 H), 4.93 (d, J=8.7 Hz, 1 H), 5.82 (m, 1 H), 7.26 (d, J=7.8 Hz, 2 H), 7.49 (d, J=7.8 Hz, 2 H), 13C NMR (75 MHz, CDCl3) −3.1, 19.9, 24.1, 25.8, 31.1, 31.5, 32.8, 62.6, 67.1, 99.1, 113.6, 128.3, 134.0, 135.0, 135.7, 143.2; HRMS (EI) calcd for C19H30O2Si 318.2015, found 318.2009.

1. temperatureThe reaction mixture was warmed to room temperature
2. stirringstirred further for 16 h
3. concentrationthe reaction mixture was concentrated under reduced pressure
4. extractionThe residue was extracted with ethyl acetate (10 mL) and brine (5 mL)
5. dry with materialthe organic layer was dried (Na2SO4)
6. concentrationconcentrated
7. customThe crude product was purified by column chromatography (1:20 ethyl acetate/hexanes)

ORD record

ord-264c537b6b914c19bcd8ac192f6f518d

Source dataset

uspto-grants-2002_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06416861B1