Lawesson's reagent → HCID 46866373, compound

HRID 1970782Notes

Reaction equation

HRID 1970782 reaction equation
[CH2:1]([C:8]1[C:9]([NH:22][C:23](=O)[CH2:24][C:25]2[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=2)=[N:10][CH:11]=[C:12]([C:14]2[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=2)[N:13]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.COC1C=CC(P2(SP(C3C=CC(OC)=CC=3)(=S)S2)=[S:41])=CC=1>C1(C)C=CC=CC=1>[CH2:1]([C:8]1[C:9]([NH:22][C:23](=[S:41])[CH2:24][C:25]2[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=2)=[N:10][CH:11]=[C:12]([C:14]2[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=2)[N:13]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

4

Reactant 2

HCID 87949Lawesson's reagentHCID 67002629HCID 67002629, compound

Product 1

HCID 46866373HCID 46866373, compoundYield 127.9%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

Under an argon atmosphere, 3-benzyl-5-(4-methoxyphenyl)-2-(phenylacetylamino)pyrazine (c-16) (539 mg, 1.32 mmol) was suspended in anhydrous toluene (50 mL) and to this was added Lawesson's reagent (320 mg, 790 μmol) while stirring at room temperature, and then heated to reflux for 17 h. After refluxing, it was cooled to room temperature, and concentrated under reduced pressure with a rotary evaporator. The residue was purified by silica gel column chromatography (55 g, n-hexane/ethyl acetate=3/1) to give 3-benzyl-5-(4-methoxyphenyl)-2-(phenylthioacetylamino)pyrazine (c-17) as a yellow amorphous powder (430 mg, 76.6%). Rf=0.33 (n-hexane/ethyl acetate=7/3). Mp. 45-47° C. UV (MeOH) λmax (log ε) 334 (4.23), 295 (4.16), 272 (4.25). UV (pH 7.4 PB) λmax(log ε) 360.5 (4.22), 283.5 (4.16). 1H NMR (400 MHz, DMSO-d6) δ 3.81 (s, 3H), 3.92 (s, 2H), 4.14 (s, 2H), 7.01 (d, J=6.8 Hz, 2H), 7.04-7.10 (AA′BB′, 2H), 7.12-7.24 (m, 3H), 7.29 (t, J=7.3 Hz, 1H), 7.37 (t, J=7.3 Hz, 2H), 7.51 (d, J=7.1 Hz, 2H), 8.05-8.10 (AA′BB′, 2H), 8.99 (s, 1H), 12.20 (s, 1H). 13C NMR (75.5 MHz, DMSO-d6) δ 39.3, 51.6, 55.3, 114.5 (2C), 126.3, 127.0, 127.6, 128.2 (2C), 128.3 (2C), 128.4 (2C), 128.9 (2C), 129.0 (2C), 136.9, 137.9, 138.0, 145.0, 149.6, 152.1, 160.9, 204.6. IR (KBr, cm−1) 700, 835, 1028, 1115, 1175, 1252, 1292, 1319, 1369, 1422, 1437, 1493, 1516, 1607, 2961, 3395. HRMS (FAB+) m/z 426.1646 (M+H, C26H24N3OS requires 426.1640).

Workup

  1. temperatureheated
  2. temperatureto reflux for 17 h
  3. temperatureAfter refluxing
  4. temperatureit was cooled to room temperature
  5. concentrationconcentrated under reduced pressure with a rotary evaporator
  6. customThe residue was purified by silica gel column chromatography (55 g, n-hexane/ethyl acetate=3/1)

Sources & evidence

ORD record
ord-78957819402a42c2811b7f36052bf757
Source dataset
uspto-grants-2013_04
Patent number
US08431525B2

Reaction notes

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