Dimethyl Sulfoxide → Ethyl 5-(1-acetyl-1H-indol-3-yl)pent-2-enoate

HRID 1198488Notes

Reaction equation

HRID 1198488 reaction equation
C(Cl)(=O)C(Cl)=O.CS(C)=O.[C:11]([N:14]1[C:22]2[C:17](=[CH:18][CH:19]=[CH:20][CH:21]=2)[C:16]([CH2:23][CH2:24][CH2:25]O)=[CH:15]1)(=[O:13])[CH3:12].CCN(CC)CC.[C:34]([CH:39]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)([O:36][CH2:37][CH3:38])=[O:35]>C(Cl)Cl.CCOCC>[CH2:37]([O:36][C:34](=[O:35])[CH:39]=[CH:25][CH2:24][CH2:23][C:16]1[C:17]2[C:22](=[CH:21][CH:20]=[CH:19][CH:18]=2)[N:14]([C:11](=[O:13])[CH3:12])[CH:15]=1)[CH3:38]

Participants

8

Reactant 5

HCID 679Dimethyl SulfoxideHCID 8471TriethylamineHCID 65578Oxalyl chlorideHCID 70670Acetic acid, 2-(triphenylphosphoranylidene)-, ethyl esterHCID 19380935HCID 19380935, compound

Product 1

HCID 53953280Ethyl 5-(1-acetyl-1H-indol-3-yl)pent-2-enoateYield 56.4%

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 6344DichloromethaneSolvent2×

Procedure

To a stirring solution of oxalyl chloride (11.4 mL, 0.13 mol) in CH2Cl2 (440 mL) at -78° C. was added dry DMSO (12.4 mL, 0.17 mol) dropwise. After 5 minutes, gas evolution ceased and the alcohol 4 (19 g, 87 mmol) in CH2Cl2 (40 mL) was added. After 30 minutes, NEt3 (73 mL, 0.52 mol) was added to effect a thick slurry. The cooling bath was removed and the reaction stirred for an additional 15 minutes before adding (carbethoxymethylene)triphenyl phosphorane (33.5 g, 96 mmol). After 2.0 hours, the reaction mixture was diluted with ether and then washed with H2O (2 times), 5% KHSO4 and brine, dried (MgSO4), and concentrated. Flash chromatography (20% ethyl acetate/hexanes) gave the olefin 5 (14 g) as a white solid. TLC Rf=0.54 (60% ethyl acetate/hexanes); 1H NMR (CDCl3) 8.42 (bd, 1H), 7.50 (d, J=7 Hz, 1H), 7.34 (t, J=7 Hz, 1H), 7.28 (t, J=7 Hz, 1H), 7.19 (bs, 1H), 7.03 (dt, J=18 and 7 Hz, 1H), 5.88 (d, J=18 Hz, 1H), 4.19 (q, J=7 Hz, 2H), 2.87 (t, J=7 HZ, 2H), 2.63 (m, 2H), 2.61 (s, 3H), 1.28 (t, J=7 Hz, 3H).

Workup

  1. waitAfter 30 minutes
  2. customThe cooling bath was removed
  3. waitAfter 2.0 hours
  4. washwashed with H2O (2 times), 5% KHSO4 and brine
  5. dry with materialdried (MgSO4)
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-7dbc55202df240a6b0437842c3c5a858
Source dataset
uspto-grants-1994_01
Patent number
US05281585

Reaction notes

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