Acetic acid, 2-(triphenylphosphoranylidene)-, ethyl ester → (E)-5,5-bis(4-fluorophenyl)-2,4-pentadienoic acid ethyl ester

HRID 1110502Notes

Reaction equation

HRID 1110502 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([C:12]2[CH:17]=[CH:16][C:15]([F:18])=[CH:14][CH:13]=2)=[CH:9][CH:10]=O)=[CH:4][CH:3]=1.[C:19]([CH:24]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)([O:21][CH2:22][CH3:23])=[O:20]>C(O)C>[CH2:22]([O:21][C:19](=[O:20])/[CH:24]=[CH:10]\[CH:9]=[C:8]([C:12]1[CH:17]=[CH:16][C:15]([F:18])=[CH:14][CH:13]=1)[C:5]1[CH:6]=[CH:7][C:2]([F:1])=[CH:3][CH:4]=1)[CH3:23].[CH2:22]([O:21][C:19](=[O:20])/[CH:24]=[CH:10]/[CH:9]=[C:8]([C:12]1[CH:17]=[CH:16][C:15]([F:18])=[CH:14][CH:13]=1)[C:5]1[CH:6]=[CH:7][C:2]([F:1])=[CH:3][CH:4]=1)[CH3:23]

Participants

5

Procedure

As described in Example 99, 3.3-bis(4-fluorophenyl)-2-propenal (9.8 g) was reacted with (carbethoxymethylene)triphenylphosphorane (14.3 g) in ethanol (20 mL) for 30 minutes at ambient temperature. The mixture of esters obtained from the usual work up was purified by HPLC (dichloromethane-hexane; 1:1) to give 2.0 g of the less polar (Z)-5,5-bis(4-fluorophenyl)-2,4-pentadienoic acid ethyl ester as an oil, and 9.3 g of (E)-5,5-bis(4-fluorophenyl)-2,4-pentadienoic acid ethyl ester. A sample of the (E)-isomer was crystallized from hexane to give the pure ester, mp 71°-72.5° C. Anal. Calculated for C19H16F2O2 : C, 72.60; H, 5.13; F, 12.09 Found: C, 72.56; H, 5.17; F, 12.36.

Workup

  1. customobtained from the usual work
  2. customup was purified by HPLC (dichloromethane-hexane; 1:1)

Sources & evidence

ORD record
ord-6453adaf3f5e4ba799c6b034f7786490
Source dataset
uspto-grants-1990_12
Patent number
US04975438

Reaction notes

Loading…