1-Penten-3-one → HCID 11323666, compound

HRID 735281Notes

Reaction equation

HRID 735281 reaction equation
Cl(O)(=O)(=O)=O.[CH:6]([C:8]([CH2:10][CH3:11])=[O:9])=[CH2:7].C([C@@H]1N[C@H](C2OC(C)=CC=2)N(C)C1=O)C1C=CC=CC=1.[CH2:32]([O:39][C:40](=[O:46])[NH:41][CH:42]=[CH:43][CH:44]=[CH2:45])[C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1>C(O)C.CCOCC>[C:8]([C@H:10]1[C@@H:42]([NH:41][C:40](=[O:46])[O:39][CH2:32][C:33]2[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=2)[CH:43]=[CH:44][CH2:45][CH2:11]1)(=[O:9])[CH2:6][CH3:7]

Participants

7

Reactant 4

HCID 153941-Penten-3-oneHCID 24247Perchloric AcidHCID 329894HCID 329894, compoundHCID 11303220(2S,5S)-(-)-5-Benzyl-3-methyl-2-(5-methyl-2-furyl)-4-imidazolidinone

Product 1

HCID 11323666HCID 11323666, compoundYield 91%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 3283Diethyl EtherSolvent

Conditions

Temperature
-30 °C

Procedure

Concentrated (70% aqueous) perchloric acid (431 μL, 5.0 mmol) was added slowly to a stirring solution of ethyl vinyl ketone (2.49 mL, 25.0 mmol) and (2S, 5S)-5-benzyl-3-methyl-2-(5-methyl-furan-2-yl)-imidazolidin-4-one (1.35 g, 5.0 mmol) pre-chilled to −30° C. Then, buta-1,3-dienyl-carbamic acid benzyl ester (4.47g, 31.3 mmol) was added dropwise over 15 minutes as a solution in 12.5 mL of absolute ethanol. After stirring for 3.5 days, the reaction was diluted with ether (150 mL), washed successively with 1N HCl (50 mL), water (50 mL) and brine (25 mL). The organic layer was then dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to afford a pale brown oil. Purification by silica gel (8:1 hexanes:ethyl acetate) afforded the title compound as a single diastereomer (as judged by HPLC analysis) in 91% yield (5.17g, 22.7 mmol) and 98% ee. The combined aqueous extracts were treated with solid K2CO3, extracted with 3×50 mL portions of CHCl3, dried over anhydrous Na2SO4 and concentrated in vacuo to afford a 91% recovery of (2S, 5S)-5-benzyl-3-methyl-2-(5-methyl-furan-2-yl)-imidazolidin-4-one (1.23 g, 4.55 mmol) after silica gel chromatography. IR (film) 3411, 3329, 3064, 3031, 2974, 2938, 2879, 2836, 1956, 1872, 1711, 1523, 1455, 1409, 1376, 1331, 1278, 1236, 1164, 1120, 1060, 1028, 988.9, 973.1, 775.6, 736.0, 697.9 cm−1; 1H NMR (300 MHz, CDCl3) δ 7.33 (m, 5H, ArH), 5.82 (m, 1H, CH═CH), 5.70 (m, 1H, CH═CH), 5.04 (m, 3H, CH2Ph and NH), 4.63 (m, 1H, CHNH), 2.86 (ddd, J=10.2, 3.9, 3.9 Hz, 1H, CHCO), 2.70 (dq, J=18.0, 7.2 Hz, 1H, one of CH2CO), 2.43 (dq, J=17.7, 7.2 Hz, 1H, one of CH2CO), 2.10-1.65 (m, 4H, CH2CH2), 1.00 (dd, J=6.9, 6.9 Hz, 3H, CH3); 13C NMR (75 MHz, CDCl3) δ 212.0, 155.9, 136.6, 130.1, 128.7, 128.2, 128.1, 126.9, 67.0, 50.4, 46.9, 34.8, 24.2, 20.7, 8.0; HRMS (CI) exact mass calc'd for (C17H21NO3) requires m/z 287.1521, found m/z 287.1519. [α]D=+122.0 (c=1.0, CHCl3). Product ratios were determined by HPLC analysis (OD-H column, 3% ethanol in hexanes, 1 mL/min, 254 nm); (1S, 6R) endo isomer tr=12.5 min, and (1R, 6S) endo isomer tr=11.3 min, exo isomers tr=8.6, 9.2 min.

Workup

  1. washwashed successively with 1N HCl (50 mL), water (50 mL) and brine (25 mL)
  2. dry with materialThe organic layer was then dried over anhydrous magnesium sulfate
  3. filtrationfiltered
  4. concentrationconcentrated in vacuo
  5. customto afford a pale brown oil
  6. customPurification by silica gel (8:1 hexanes:ethyl acetate)

Sources & evidence

ORD record
ord-146198bcf3d04f4abccde464a83d6b15
Source dataset
uspto-grants-2009_09
Patent number
US07592463B2

Reaction notes

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