4-Nitrobenzaldehyde → 4-Methyl-1-(4-nitrophenyl)pent-2-yne-1,4-diol

Temperature

-78 °C

To a stirred −78° C. solution of 2-methylbut-3-yn-2-ol (6.1 mL, 63.5 mmol, 1.2 eq) in dry THF (250 mL), n-BuLi (62 mL, 2.3 M in hexane, 142 mmol, 2.7 eq) was added dropwise over 10 minutes under an inert atmosphere. After being stirred for 40 min at −78° C., a solution of 4-nitrobenzaldehyde (8 g, 52.9 mmol, 1 eq) in dry THF (50 mL) was added to the reaction mixture and stirring was continued for an additional 1 h at −78° C. The reaction mixture was then quenched with a saturated NH4Cl solution and extracted with EtOAc (2×200 mL). The combined organic layers were washed with water (200 mL) and brine (100 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The resulting residue was purified by column chromatography (30% ethyl acetate in hexanes) to afford 4-methyl-1-(4-nitrophenyl)pent-2-yne-1,4-diol (8 g, 65%) as a yellow solid.

1. stirringstirring
2. waitwas continued for an additional 1 h at −78° C
3. customThe reaction mixture was then quenched with a saturated NH4Cl solution
4. extractionextracted with EtOAc (2×200 mL)
5. washThe combined organic layers were washed with water (200 mL) and brine (100 mL)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe resulting residue was purified by column chromatography (30% ethyl acetate in hexanes)

ORD record

ord-2531a06588f841a785d9180b53eb60e8

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08071595B2