Ammonium Chloride → 4-Ethynyloxan-4-ol

A stirred solution of dihydro-2H-pyran-4(3H)-one (500 mg, 5.0 mmol) in dry THF (20 mL) was cooled to −70° C. and 0.5 M ethynylmagnesium chloride in THF (20 mL, 10 mmol) was added in a slow stream. The cooling bath was allowed to expire and the mixture was stirred as it warmed to rt. After 6 h, satd aq NH4Cl (20 mL) was added and the mixture was concentrated on the rotary evaporator. The aqueous residue was extracted with EtOAc (2×50 mL). The combined organic extracts were washed with brine, dried over Na2SO4 and concentrated to leave crude 4-ethynyltetrahydro-2H-pyran-4-ol (491 mg, 78%) as a brown oil. 1H NMR (CDCl3) 1.80 (m, 2H), 1.92 (m, 2H), 2.57 (s, 1H), 3.68 (m, 2H), 3.90 (m, 2H).

1. additionwas added
2. concentrationthe mixture was concentrated on the rotary evaporator
3. extractionThe aqueous residue was extracted with EtOAc (2×50 mL)
4. washThe combined organic extracts were washed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated

ORD-Eintrag

ord-cfb7f9444b054bac963ee380e46a2402

Quelldatensatz

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08883778B2