Methyl-4-oxo-4-phenyl-2-butenoate → HCID 59445881, compound
Reaction equation
[Si:1]([O:8][CH2:9][CH:10](Cl)[CH:11]=[O:12])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[O:14]=[C:15]([C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)/[CH:16]=[CH:17]/[C:18]([O:20][CH3:21])=[O:19]>>[Si:1]([O:8][CH2:9][C@H:10]1[C@@H:17]([C:18]([O:20][CH3:21])=[O:19])[CH:16]=[C:15]([C:22]2[CH:23]=[CH:24][CH:25]=[CH:26][CH:27]=2)[O:14][C:11]1=[O:12])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]Participants
Procedure
Prepared according to the general procedure from 3-(tert-butyldimethylsilyloxy)-2-chloropropanal and (E)-methyl 4-oxo-4-phenylbut-2-enoate using 0.5 mol % 1 as the catalyst in 80% yield as a 3:1 mixture of diastereomers. The diastereomers were separated by silica gel chromatography (15:1 hexanes/EtOAc) and characterized separately. [α]D20 (c 1.07, CHCl3)=+133.6; 1H NMR (400 MHz, CDCl3) δ 7.65-7.62 (m, 2H), 7.40-7.37 (m, 3H), 5.94 (d, 1H, J=7.1 Hz), 4.26 (dd, 1H, J=10.6, 5.7 Hz), 3.88 (t, 1H, J=10.1 Hz), 3.76 (dd, 1H, J=13.7, 7.4 Hz), 3.72 (s, 3H), 3.08-3.02 (m, 1H), 0.89 (s, 9H), 0.07 (s, 3H), 0.06 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 170.9, 167.7, 152.5, 131.9, 129.8, 128.8, 125.0, 98.1, 59.7, 52.6, 42.5, 38.7, 25.9, 18.4, −5.4, −5.6; IR (thin film) ν 3062, 2953, 2929, 2886, 2857, 1778, 1739, 1254, 1197, 1176 cm−1; HRMS (EI) calcd for C20H25O5Si [M]+ 376.1706, found 376.1697; 97% ee (3R,4S)-isomer as determined by HPLC (AD-H, 100:1 hexanes/i-PrOH), tr (3R,4S)=21.8 min, tr (3S,4R)=15.2 min.
Workup
- customPrepared
- customThe diastereomers were separated by silica gel chromatography (15:1 hexanes/EtOAc)
- customas determined by HPLC (AD-H, 100:1 hexanes/i-PrOH), tr (3R,4S)=21.8 min, tr (3S,4R)=15.2 min.
Sources & evidence
- ORD record
- ord-33c6e2fefe1c4eecbafe69763df1f963
- Source dataset
- uspto-grants-2013_08
- Patent number
- US08501658B2
Reaction notes
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