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ChemicalBook CAS DataBase List (3R,4S)-tert-Butyl 2-oxo-4-phenyl-3-(triethylsilyloxy)azetidine-1-carboxylate
149198-47-0

(3R,4S)-tert-Butyl 2-oxo-4-phenyl-3-(triethylsilyloxy)azetidine-1-carboxylate synthesis

4synthesis methods
-

Yield:149198-47-0 2.4 g (Y: 83%)

Reaction Conditions:

with dmap;N-ethyl-N,N-diisopropylamine in tetrahydrofuran;ethyl acetate;

Steps:

12 (3R,4S) -1-t-Butoxycarbonyl-4-phenyl-3-triethylsilyloxy-2-azetidinone (IVa) STR12

EXAMPLE 12 (3R,4S) -1-t-Butoxycarbonyl-4-phenyl-3-triethylsilyloxy-2-azetidinone (IVa) STR12 To a stirred solution of (3R,4S)-4-phenyl-3-triethylsilyloxy-2-azetidinone (XXII) (2.200 g, 7.92 mmol) in dry THF (25 mL) was added N,N-diisopropylethylamine (1.65 mL. 9.510 mmol, 1.2 equiv) at 0° C. under an argon atmosphere. The solution was stirred for 5 min followed by the addition of di-t-butyldicarbonate (2.080 g, 9.510 mmol, 1.2 equiv) and 4-dimethylaminopyridine (193.6 mg, 1.581 mmol, 0.20 equiv). The reaction mixture was stirred at 0° C. for 60 min. The solution was diluted by adding ethyl acetate (25 mL). The resulting solution was washed with brine, 10% NaHC3, 10% HCl solution, dried (MgSO4), and concentrated to give a crude compound (oil). The compound was further purified by silica gel flash chromatography (eluted with 15% ethyl acetate in hexanes) to afford 2.4 g (Y: 83%) of the title β-lactam as a white solid; 1 H-NMR (CDCl3) δ7.28 (m, 5H) 5.03 (m, 2H) 1.39 (s, 9H) 0.76 (t, J=7.6 Hz, 9H) 0.43 (m, 6H).

References:

US5478854,1995,A

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