(Methoxymethyl)phosphonium chloride → (2S,4S,5S)-4-methoxy-5-methyl-3-methoxymethylene-2-nonyltetrahydro-2H-pyran

HRID 2399565Notes

Reaction equation

HRID 2399565 reaction equation
[Cl-].[CH3:2][O:3][CH2:4][PH3+].[Li]CCCC.[CH3:11][O:12][C@H:13]1[C@@H:18]([CH3:19])[CH2:17][O:16][C@@H:15]([CH2:20][CH2:21][CH2:22][CH2:23][CH2:24][CH2:25][CH2:26][CH2:27][CH3:28])[C:14]1=O>O1CCCC1.C(OCC)(=O)C>[CH3:2][O:3][C@H:4]1[C@@H:18]([CH3:19])[CH2:17][O:16][C@@H:15]([CH2:20][CH2:21][CH2:22][CH2:23][CH2:24][CH2:25][CH2:26][CH2:27][CH3:28])[C:14]1=[CH:13][O:12][CH3:11]

Participants

6

Conditions

Temperature
0 °C

Procedure

To a stirred suspension of methoxymethylphosphonium chloride (1,130 mg) in dry tetrahydrofuran (3 ml) there was added n-BuLi (1.9 ml, 1.6M in n-hexane) at 0° C. After the mixture was stirred at 0° C. for 30 min, a solution of (2S,4S,5S)-4-methoxy-5-methyl-2-nonyltetrahydro-2H-pyran-3-one (273 mg) in dry tetrahydrofuran (3 ml) was added to the resulting deep orange solution. After 30 min, the mixture was allowed to warm to room temperature, and stirred for an additional 2 hrs. The reaction was quenched by addition of saturated aqueous ammonium chloride solution. The mixture was extracted with diethyl ether, and the combined organic extracts were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated. Purification of the residue by silica gel chromatography (n-hexane: ethyl acetate=10:1 as an eluent) gave (2S,4S,5S)-4-methoxy-5-methyl-3-methoxymethylene-2-nonyltetrahydro-2H-pyran (249 mg,83% yield).

Workup

  1. waitAfter 30 min
  2. temperatureto warm to room temperature
  3. stirringstirred for an additional 2 hrs
  4. customThe reaction was quenched by addition of saturated aqueous ammonium chloride solution
  5. extractionThe mixture was extracted with diethyl ether
  6. washthe combined organic extracts were washed with brine
  7. dry with materialdried over anhydrous sodium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated
  10. customPurification of the residue by silica gel chromatography (n-hexane

Sources & evidence

ORD record
ord-ade2f49cb44a4d4b8d358c01030ef2d0
Source dataset
uspto-grants-1995_09
Patent number
US05449785

Reaction notes

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