Tetraisopropyl methylenediphosphonate → diisopropyl (E)-4-(t-butyldimethylsilyloxy)but-1-enylphosphonate

HRID 1708081Notes

Reaction equation

HRID 1708081 reaction equation
[CH2:1]([P:12](=[O:21])([O:17][CH:18]([CH3:20])[CH3:19])[O:13][CH:14]([CH3:16])[CH3:15])P(=O)(OC(C)C)OC(C)C.C([Li])CCC.[Si:27]([O:34][CH2:35][CH2:36][CH:37]=O)([C:30]([CH3:33])([CH3:32])[CH3:31])([CH3:29])[CH3:28]>CCCCCCC>[Si:27]([O:34][CH2:35][CH2:36]/[CH:37]=[CH:1]/[P:12](=[O:21])([O:13][CH:14]([CH3:15])[CH3:16])[O:17][CH:18]([CH3:19])[CH3:20])([C:30]([CH3:31])([CH3:32])[CH3:33])([CH3:29])[CH3:28]

Participants

5

Reactant 3

HCID 74266Tetraisopropyl methylenediphosphonateHCID 36623923-((Tert-butyldimethylsilyl)oxy)propanalHCID 178418339Butyllithium

Product 1

HCID 10020796diisopropyl (E)-4-(t-butyldimethylsilyloxy)but-1-enylphosphonateYield 53.6%

Reagents, catalysts & solvents 1

HCID 8900HeptaneSolvent

Procedure

To a solution of tetraisopropyl methylenebisphosphonate (2.50 g, 7.26 mmol) in n-heptane (50 ml) was added n-butyllithium (2.70 ml of 2.7M solution in n-hexanes; 7.29 mmol) and the mixture stirred at room temperature under dry nitrogen for 15 min. To the solution was added crude 3-(t-butyldimethylsilyloxy) propanal (approx. 5.85 mmol) and the mixture heated under reflux for 0.5 hr then stirred at room temperature for 64 hr. The mixture was filtered then the solvent removed. The residue was purified by column chromatography on silica gel eluting with dichloromethane-ethyl acetate (9:1, 4:1) to afford diisopropyl (E)-4-(t-butyldimethylsilyloxy)but-1-enylphosphonate as a colourless oil (1.10 g, 43%); νmax (film) 2940, 1625, 1460, 1380, 1250, 1105, 980 and 830 cm-1 ; δH (CDCl3) 0.03 (6H, s, SiCH3), 0.90 (9H, s, C(CH3)3), 1.32 (12H, dd, J 3 Hz and 6 Hz, CH(CH3)2), 2.43 (2H, m, CH2), 3.72 (2H, t, J 7 Hz, CH2O ), 4.65 (2H, m, CH(CH3)2), 5.72 (1H, dd, J 17 Hz and 20 Hz, PCH=CH), 6.75 (1H, ddt, J 7 Hz, 17 Hz and 20 Hz, PCH=CH); FABMS(thioglycerol) 351 (MH+) (Found: C, 54.76; H, 10.05%. C16H35O4PSI requires C, 54.84; H, 10.07%).

Workup

  1. temperaturethe mixture heated
  2. temperatureunder reflux for 0.5 hr
  3. stirringthen stirred at room temperature for 64 hr
  4. filtrationThe mixture was filtered
  5. customthe solvent removed
  6. customThe residue was purified by column chromatography on silica gel eluting with dichloromethane-ethyl acetate (9:1, 4:1)

Sources & evidence

ORD record
ord-2579c2fca5a3453182df7febc32e1986
Source dataset
uspto-grants-1994_10
Patent number
US05356886

Reaction notes

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