Diisopropylamine → HCID 23358054, compound

HRID 233798Notes

Reaction equation

HRID 233798 reaction equation
C(NC(C)C)(C)C.[Li]CCCC.CCCCCC.[Cl:19][C:20]1[CH:25]=[CH:24][CH:23]=[C:22]([Cl:26])[C:21]=1[CH2:27][C:28]#[N:29].[CH2:30]([O:32][C:33](=[O:37])[CH2:34][CH2:35]Br)[CH3:31]>C1COCC1>[CH2:30]([O:32][C:33](=[O:37])[CH2:34][CH2:35][CH:27]([C:28]#[N:29])[C:21]1[C:20]([Cl:19])=[CH:25][CH:24]=[CH:23][C:22]=1[Cl:26])[CH3:31]

Participants

7

Reactant 5

HCID 7912DiisopropylamineHCID 8058HexaneHCID 68320Ethyl 3-bromopropionateHCID 76678(2,6-Dichlorophenyl)acetonitrileHCID 178418339Butyllithium

Product 1

HCID 23358054HCID 23358054, compoundYield 95.8%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
-78 °C

Procedure

A solution of diisopropylamine (19.2 mL, 0.135 mol) in THF (75 mL) was added dropwise at room temperature to n-BuLi in hexane (67.5 mL, 0.135 mol) under argon atmosphere. The mixture was stirred for 0.5 h and then brought to -78° C.C. A solution of 2,6-dichlorophenyl acetonitrile (25 g, 0.135 mol) in THF (50 mL) was added dropwise while the reaction mixture was maintained at -78° C.C. The resulting mixture was stirred for 1 h, whereafter a solution of ethyl-3-bromoproionate (17.2 mL, 0.135 mol) in THF (50 mL) was added dropwise. The resulting mixture was stirred for 1 h, and then allowed to reach room temperature. After an additional 1 h at 25° C.C., the mixture was quenched with 10% aqueous hydrochloride solution. The phases were separated and the aqueous phase was extracted with diethyl ether (3×75 mL). The combined organic phases were dried (MgSO4), filtered, and concen-trated in vacuo affording ethyl-4-cyano-4-(2,6-dichlorophenyl)-butanoate (37 g) as an oil. A solution of the butanoate (3.53 g, 15 mmol) in HCl-saturated ethanol (100 mL) was hydrogenated at 50 psi over PtO2 (0.9 g) in a Parr apparatus. Removal of the catalyst by filtration, followed by evaporation of the EtOH, yielded an oily residue. The oil was taken up in 15% NaOH and was extracted with diethylether (3×30 mL), dried, filtered, and concentrated in vacuo. The oily residue was purified by flash chromatography using CH2Cl2 /MeOH (19/1) as eluent, affording pure racemic-69 (0.9 g, 85%): MS m/e 244.95 (M+ +1, 15.1), 243.95 (M+, 3.5), 242.95 (M+ -1, 24.1), 208.00 (19.3), 179.00 (29.3), 173.9 (61.3), 171.9 (100), 137.00 (31.6), 115.00 (20.5)

Workup

  1. custombrought to -78° C
  2. additionwas added dropwise
  3. stirringThe resulting mixture was stirred for 1 h
  4. customto reach room temperature
  5. waitAfter an additional 1 h at 25° C
  6. custom, the mixture was quenched with 10% aqueous hydrochloride solution
  7. customThe phases were separated
  8. extractionthe aqueous phase was extracted with diethyl ether (3×75 mL)
  9. dry with materialThe combined organic phases were dried (MgSO4)
  10. filtrationfiltered

Sources & evidence

ORD record
ord-ed53bca1d25f4111848e4170464f94c2
Source dataset
uspto-grants-1997_01
Patent number
US05594024

Reaction notes

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