1,1,3,3-Tetramethylguanidine → Methyl 2-(benzyloxycarbonylamino)-2-(1,4-dioxaspiro[4.5]decan-8-ylidene)acetate

HRID 68289Notes

Reaction equation

HRID 68289 reaction equation
[O:1]1[C:5]2([CH2:10][CH2:9][C:8](=O)[CH2:7][CH2:6]2)[O:4][CH2:3][CH2:2]1.[CH2:12]([O:19][C:20]([NH:22][CH:23](P(OC)(OC)=O)[C:24]([O:26][CH3:27])=[O:25])=[O:21])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1.CN(C)C(N(C)C)=N>CCOC(C)=O>[CH2:12]([O:19][C:20]([NH:22][C:23](=[C:8]1[CH2:9][CH2:10][C:5]2([O:4][CH2:3][CH2:2][O:1]2)[CH2:6][CH2:7]1)[C:24]([O:26][CH3:27])=[O:25])=[O:21])[C:13]1[CH:14]=[CH:15][CH:16]=[CH:17][CH:18]=1

Participants

5

Procedure

A solution of 1,4-dioxaspiro[4.5]decan-8-one (15 g, 96 mmol) in EtOAc (150 mL) was added to a solution of methyl 2-(benzyloxycarbonylamino)-2-(dimethoxyphosphoryl)acetate (21.21 g, 64.0 mmol) in 1,1,3,3-tetramethylguanidine (10.45 mL, 83 mmol) and EtOAc (150 mL). The resulting solution was the stirred at ambient temperature for 72 h and then it was diluted with EtOAc (25 mL). The organic layer was washed with 1N HCl (75 mL), H2O (100 mL) and brine (100 mL), dried (MgSO4), filtered and concentrated. The residue was purified via Biotage (5% to 25% EtOAc/Hexanes; 300 g column). The combined fractions containing the product were then concentrated under vacuum and the residue was re-crystallized from hexanes/EtOAc to give white crystals that corresponded to methyl 2-(benzyloxycarbonylamino)-2-(1,4-dioxaspiro[4.5]decan-8-ylidene)acetate (6.2 g) 1H NMR (400 MHz, CDCl3-d) δ ppm 7.30-7.44 (5H, m), 6.02 (1H, br. s.), 5.15 (2H, s), 3.97 (4H, s), 3.76 (3H, br. s.), 2.84-2.92 (2H, m), 2.47 (2H, t, J=6.40 Hz), 1.74-1.83 (4H, m). LC (Cond. OL1): Rt=2.89 min. LC/MS: Anal. Calcd. For [M+Na]+ C19H23NNaO6: 745.21. found: 745.47.

Workup

  1. washThe organic layer was washed with 1N HCl (75 mL), H2O (100 mL) and brine (100 mL)
  2. dry with materialdried (MgSO4)
  3. filtrationfiltered
  4. concentrationconcentrated
  5. customThe residue was purified via Biotage (5% to 25% EtOAc/Hexanes; 300 g column)
  6. additionThe combined fractions containing the product
  7. concentrationwere then concentrated under vacuum
  8. customthe residue was re-crystallized from hexanes/EtOAc

Sources & evidence

ORD record
ord-b2ebd5a180e4441985f8a88823bef475
Source dataset
uspto-grants-2014_09
Patent number
US08822444B2

Reaction notes

Loading…