Triethylamine → (1S,2S) 2-Ethyl-1-(2trimethylsilanylethoxycarbonylamino)cyclopropane-carboxylic acid tert-butyl ester

HRID 719841Notes

Reaction equation

HRID 719841 reaction equation
[C:1]([O:5][C:6]([C:8]1(C(O)=O)[CH2:10][CH:9]1[CH2:11][CH3:12])=[O:7])([CH3:4])([CH3:3])[CH3:2].CC[N:18]([CH2:21]C)CC.C1C=CC(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:30])=CC=1.[CH3:40][Si:41]([CH3:46])([CH3:45])[CH2:42][CH2:43][OH:44]>C1C=CC=CC=1>[C:1]([O:5][C:6]([C@:8]1([NH:18][C:21]([O:44][CH2:43][CH2:42][Si:41]([CH3:46])([CH3:45])[CH3:40])=[O:30])[CH2:10][C@@H:9]1[CH2:11][CH3:12])=[O:7])([CH3:2])([CH3:3])[CH3:4]

Participants

6

Reactant 4

HCID 8471TriethylamineHCID 180132-(Trimethylsilyl)ethanolHCID 199401P,P-Diphenylphosphinic azideHCID 666701131-(tert-Butoxycarbonyl)-2-ethylcyclopropane-1-carboxylic acid

Product 1

HCID 86601847(1S,2S) 2-Ethyl-1-(2trimethylsilanylethoxycarbonylamino)cyclopropane-carboxylic acid tert-butyl esterYield 238%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

To a suspension, of the product of Step 2 (10 g, 46.8 mmol) and 3 g of freshly activated 4A molecular sieves in dry benzene (160 mL), was added Et3N (7.50 mL, 53.8 mmol) and DPPA (11 mL, 10.21 mmol). The reaction mixture was refluxed for 3.5 h, 2-trimethylsilyl-ethanol (13.5 mL, 94.2 mmol) was then added, and the reaction mixture was refluxed overnite. The reaction mixture was filtered, diluted with Et2O, washed with a 10% aqueous citric acid solution, water, saturated aqueous NaHCO3, water (2×), brine (2×), dried (MgSO4) and concentrated in vacuo. The residue was suspended with 10 g of Aldrich polyisocyanate scavenger resin in 120 mL of CH2Cl2, stirred at rt overnite and filtered to afford the titled product (8 g, 24.3 mmol; 52%) as a pale yellow oil: 1H NMR (CDCl3) δ 0.03 (s, 9H), 0.97 (m, 5H), 1.20 (bm, 1H), 1.45 (s, 9H), 1.40–1.70 (m, 4H), 4.16 (m, 2H), 5.30 (bs, 1H).

Workup

  1. temperatureThe reaction mixture was refluxed for 3.5 h
  2. temperaturethe reaction mixture was refluxed overnite
  3. filtrationThe reaction mixture was filtered
  4. additiondiluted with Et2O
  5. washwashed with a 10% aqueous citric acid solution, water, saturated aqueous NaHCO3, water (2×), brine (2×)
  6. dry with materialdried (MgSO4)
  7. concentrationconcentrated in vacuo
  8. filtrationfiltered

Sources & evidence

ORD record
ord-dd61e106dc9440cb991f004ff0cc20a8
Source dataset
uspto-grants-2006_11
Patent number
US07132504B2

Reaction notes

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