p-Toluenesulfonic acid monohydrate → (2S,4R,E) 4,5-Bis(4-fluorophenyl)-1-[(4-methyl-1,3-dioxan-2-yl)ethenyl]-2-(1-methylethyl)-1H-imidazole

HRID 892964Notes

Reaction equation

HRID 892964 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[N:9]=[C:10]([CH:24]([CH3:26])[CH3:25])[N:11](/[CH:20]=[CH:21]/[CH:22]=[O:23])[C:12]=2[C:13]2[CH:18]=[CH:17][C:16]([F:19])=[CH:15][CH:14]=2)=[CH:4][CH:3]=1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1.[CH2:39](O)[CH2:40][C@H:41]([OH:43])[CH3:42]>C1(C)C=CC=CC=1>[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:8]2[N:9]=[C:10]([CH:24]([CH3:26])[CH3:25])[N:11](/[CH:20]=[CH:21]/[C@@H:22]3[O:43][C@H:41]([CH3:42])[CH2:40][CH2:39][O:23]3)[C:12]=2[C:13]2[CH:18]=[CH:17][C:16]([F:19])=[CH:15][CH:14]=2)=[CH:6][CH:7]=1

Participants

5

Reactant 3

HCID 521998p-Toluenesulfonic acid monohydrateHCID 637497(-)-1,3-ButanediolHCID 14849786(E)-3-[4,5-bis(4-fluorophenyl)-2-(1-methylethyl)-1H-imidazol-1-yl]-2-propenal

Product 1

HCID 14849807(2S,4R,E) 4,5-Bis(4-fluorophenyl)-1-[(4-methyl-1,3-dioxan-2-yl)ethenyl]-2-(1-methylethyl)-1H-imidazoleYield 73.5%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A mixture of (E)-3-[4,5-bis(4-fluorophenyl)-2-(1-methylethyl)-1H-imidazol-1-yl]-2-propenal (2.01 g), p-toluenesulphonic acid monohydrate (0.316 g) and (R)-(-)-butane-1,3-diol (98%, 1.37 g) in toluene (130 ml) was heated under reflux with a Dean-Stark trap for 20 h. The mixture was concentrated to ca. 30 ml and purified by FCC eluting with System A (1:4) to give the title product (1.78 g,) as a white solid. δ(CDCl3) 1.23 (d, J 6 Hz, 3H, CH3CH--O), 1.42 (d, J 7 Hz, 6H, (CH3)2CH), 1.55-1.8 (m, 2H, OCH(CH3)CH2CH2O), 3.20 (septet, J 7 Hz, 1H, (CH3)2CH), 3.7-3.9 (m, 2H, CH2O), 4.05-4.16 (m, 1H, O--CH(CH3)), 4.95 (d, J 5 Hz, 1H, CH=CHCH(O)2), 5.32 (dd, J 15 and 5 Hz, 1H, NCH=CH), 6.76 (dd, J 15 and 1 Hz, 1H, NCH=CH), 6.89 (t, J 9 Hz, 2H, C-3 and C-5 protons of 4-(4-fluorophenyl)), 7.11 (t, J 9 Hz, 2H, C-3 and C-5 protons of 5-(4-fluorophenyl)), 7.39 and 7.27 (2 dd, J 9 and 6 Hz, 4H, C-2 and C-6 protons of both 4-fluorophenyls).

Workup

  1. temperaturewas heated
  2. temperatureunder reflux with a Dean-Stark trap for 20 h
  3. concentrationThe mixture was concentrated to ca. 30 ml
  4. custompurified by FCC
  5. washeluting with System A (1:4)

Sources & evidence

ORD record
ord-ba46d69f55db4e43b0a811ca9b23893b
Source dataset
uspto-grants-1992_06
Patent number
US05120848

Reaction notes

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