(Triisopropylsilyl)acetylene → 5-Phenyl-1-(triisopropylsilyl)pent-1-yn-3-one

Temperature

0 °C

Following a procedure of Trost (Trost, B. M. et al., J. Am. Chem. Soc. 128, 6745-6754 (2006)); n-Butyllithium (2.5 M in hexanes, 10.4 ml, 26 mmol, 1.7 eq.) was added dropwise to a solution of triisopropylsilyl acetylene (5.8 ml, 26 mmol, 1.7 eq.) in THF (53 ml) at −78° C. After addition, the mixture was allowed to warm slowly to 0° C. and stirred for 1 h. The mixture was cooled to −78° C. and a solution of 83 (3.0 g, 15.3 mmol, 1 eq.) in THF (20 ml) was added dropwise. The mixture was then allowed to slowly warm to −10° C. and stirred for 1 h before being quenched by the addition of saturated aq. NH4Cl (50 ml). The mixture was extracted with EtOAc (3×30 ml) and the combined organic phases were washed with brine (50 ml) before being dried (MgSO4), filtered and concentrated to give the crude product. This was purified by column chromatography on silica, eluting with petrol/Et2O (100:0 to 98:2), giving the title product 84 as a clear, colourless oil (4.61 g, 96%).

1. additionAfter addition
2. temperatureThe mixture was cooled to −78° C.
3. temperatureto slowly warm to −10° C.
4. stirringstirred for 1 h
5. custombefore being quenched by the addition of saturated aq. NH4Cl (50 ml)
6. extractionThe mixture was extracted with EtOAc (3×30 ml)
7. washthe combined organic phases were washed with brine (50 ml)
8. dry with materialbefore being dried (MgSO4)
9. filtrationfiltered
10. concentrationconcentrated
11. customto give the crude product
12. customThis was purified by column chromatography on silica
13. washeluting with petrol/Et2O (100:0 to 98:2)

ORD record

ord-af10c029f4c84a9493c7ea9dbc2ef903

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09242954B2