반응 #155471

반응 방정식

1,4-dioxaspiro[4.5]decan-8-one

methyl 2-(benzyloxycarbonylamino)-2-(dimethoxyphosphoryl)acetate

1,1,3,3-tetramethylguanidine

→

methyl 2-(benzyloxycarbonylamino)-2-(1,4-dioxaspiro[4.5]decan-8-ylidene)acetate

수율 26.8%

용매

EtOAc

EtOAc

EtOAc

반응 조건

후처리

1. 1
   세척The organic layer was washed with 1N HCl (75 mL), H2O (100 mL) and brine (100 mL)
2. 2
   건조dried (MgSO4)
3. 3
   여과filtered
4. 4
   농축concentrated
5. 5
   기타The residue was purified via Biotage (5% to 25% EtOAc/Hexanes; 300 g column)
6. 6
   workup.ADDITIONThe combined fractions containing the product
7. 7
   농축were then concentrated under vacuum
8. 8
   기타the residue was re-crystallized from hexanes/EtOAc

실험 절차

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.

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