2-Bromo-3-methyl-2-cyclopenten-1-ol → 2-Ethyl-3-methyl-cyclopent-2-enol

HRID 1178392

反応式

HRID 1178392 の反応式
Br[C:2]1[CH:3]([OH:8])[CH2:4][CH2:5][C:6]=1[CH3:7].[CH2:9]([Mg]Br)[CH3:10]>C1COCC1.[Ni](Cl)Cl.C1(P(C2C=CC=CC=2)CCCP(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[CH2:9]([C:2]1[CH:3]([OH:8])[CH2:4][CH2:5][C:6]=1[CH3:7])[CH3:10]

参加物

5

反応物 2

HCID 107497992-Bromo-3-methyl-2-cyclopenten-1-olHCID 178418443HCID 178418443、化合物

生成物 1

HCID 219861782-Ethyl-3-methyl-cyclopent-2-enol

試薬・触媒・溶媒 2

HCID 2724937Dichloro(1,1'-(1,3-propanediyl)bis(1,1-diphenylphosphine-kappaP))nickel触媒HCID 8028Tetrahydrofuran溶媒

実験手順

The alcohol (Intermediate V2, 16 mmol) in THF (30 mL) at 0° C. was treated with ethyl magnesium bromide (40 mmol). The catalyst, 1,3-bis(diphenylphosphino)propane nickel (II) chloride (0.75 mmol) (NiCl2dppp) was added in one portion and the mixture was heated to reflux for 3 hours following the procedure of Organ et al. J. Org. Chem. 1997, 62, 1523, incorporated herein by reference.) The reaction mixture was cooled to rt and quenched with sat. NH4Cl solution. The mixture was filtered and partitioned between brine and diethyl ether. The organic layer was removed and dried over Na2SO4, filtered and concentrated under vacuum. The oil was purified by chromatography on SiO2 with 20% EtOAc:Hx to yield 2-ethyl-3-methyl-cyclopent-2-enol (Intermediate V3). Use of the alcohol (Intermediate V3) in the applicable steps of Method A and Method P produced 4-(2-ethyl-3-methyl-cyclopent-2-enylmethyl)-1,3-dihydro-imidazol-2-one (Compound 64). 1H NMR (300 MHz, CD3OD-d4): δ 6.03 (s, 1H), 2.88 (brs, 1H), 2.65-2.59 (m, 1H), 2.27-1.83 (series of m, 6H), 1.62 (s, 3H), 1.54-1.45 (m, 1H), 0.97 (t, J=6 Hz, 3H).

後処理

  1. temperaturethe mixture was heated
  2. temperatureto reflux for 3 hours
  3. customquenched with sat. NH4Cl solution
  4. filtrationThe mixture was filtered
  5. custompartitioned between brine and diethyl ether
  6. customThe organic layer was removed
  7. dry with materialdried over Na2SO4
  8. filtrationfiltered
  9. concentrationconcentrated under vacuum
  10. customThe oil was purified by chromatography on SiO2 with 20% EtOAc

出典と根拠

ORDレコード
ord-15bcdaa8bd04498892b4b56ccf4c36ce
出典データセット
uspto-grants-2007_10
特許番号
US07276522B2

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