反应详情

A solution of 740 mg (2.118 mmol) [5-(3-azido-phenyl)-5-fluoromethyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]carbamic acid tert-butyl ester (Example 31h) in 5 ml THF and 5 ml EtOH was stirred in the presence of 35 mg 10% Pd—C under hydrogen. After 3 h the mixture was filtered over celite, concentrated and crystallized from EtOAc/hexane to give a beige solid. The racemic product was separated via prep HPLC on Chiralpak AD-H 250×4.6 mm column using heptan/EtOH 1:1 as an eluent. The desired compound was the slower eluting (R)-enantiomer. TLC: Rf (Hexane/EtOAc 2:1)=0.15. HPLC: RtH4=1.764 min; ESIMS [M+H]+=324.11 1H-NMR (CDCl3, 360 MHz, broad signals due to hindered rotation): 10.5 (br, 1H), 7.12 (br, 1H), 6.69 (d, 1H), 6.59 (br d, 1H), 4.8-4.0 (m, 8H), 1.48 (br s, 9H).

1. filtrationAfter 3 h the mixture was filtered over celite,
2. concentrationconcentrated
3. customcrystallized from EtOAc/hexane
4. customto give a beige solid
5. customThe racemic product was separated via prep HPLC on Chiralpak AD-H 250×4.6 mm column
6. washslower eluting (R)-enantiomer
7. customRtH4=1.764 min