Diisopropylamine → Lithium diisopropylamide

HRID 1451155Notes

Reaction equation

HRID 1451155 reaction equation
C([Li:5])CCC.[CH:6]([NH:9][CH:10]([CH3:12])[CH3:11])([CH3:8])[CH3:7].[C:13]1([CH:19]([C:24]2[N:29]=[C:28]([O:30][CH3:31])[CH:27]=[C:26]([O:32][CH3:33])[N:25]=2)[C:20]([O:22][CH3:23])=[O:21])[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1.C1(C)C=CC(S([C:43]#[N:44])(=O)=O)=CC=1.[Cl-].[NH4+]>O1CCCC1>[CH:6]([N-:9][CH:10]([CH3:12])[CH3:11])([CH3:8])[CH3:7].[Li+:5].[C:43]([C:19]([C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)([C:24]1[N:29]=[C:28]([O:30][CH3:31])[CH:27]=[C:26]([O:32][CH3:33])[N:25]=1)[C:20]([O:22][CH3:23])=[O:21])#[N:44]

Participants

8

Reactant 5

HCID 7912DiisopropylamineHCID 25517Ammonium ChlorideHCID 87946p-Toluenesulphonyl cyanideHCID 19973938HCID 19973938, compoundHCID 178418339Butyllithium

Product 2

HCID 2724682Lithium diisopropylamideHCID 19973939HCID 19973939, compound

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-65 °C

Procedure

Lithium diisopropylamide was prepared by adding a solution of n-butyllithium (4 ml, 2.5M in hexane) slowly by syringe into a solution of diisopropylamine (1.01 g) in dry tetrahydrofuran (20 ml) at -65° C. under nitrogen. After stirring at -65° C. for 20 minutes, a solution of methyl 2-phenyl-2-(4,6-dimethoxypyrimidin-2-yl)acetate (2.88 g) in dry tetrahydrofuran (10 ml) was added by syringe. The solution was again stirred for 20 minutes, after which p-toluenesulfonyl cyanide (1.81 g) was added in one portion. The mixture was allowed to warm to room temperature, and was stirred for 3 hours. It was then poured into saturated ammonium chloride solution. The product was extracted with diethyl ether (2×50 ml), dried, evaporated to dryness under vacuum, and flash chromatographed on silica gel, eluting with ethyl acetate/60°-80° petroleum ether (1:4), to give 0.9 g of the desired product as a white solid, mp 91°-93° C.

Workup

  1. stirringThe solution was again stirred for 20 minutes
  2. temperatureto warm to room temperature
  3. stirringwas stirred for 3 hours
  4. extractionThe product was extracted with diethyl ether (2×50 ml)
  5. customdried
  6. customevaporated to dryness under vacuum, and flash
  7. customchromatographed on silica gel
  8. washeluting with ethyl acetate/60°-80° petroleum ether (1:4)

Sources & evidence

ORD record
ord-a8b8df91bb1b44d4b877804b32802777
Source dataset
uspto-grants-1997_02
Patent number
US05604181

Reaction notes

Loading…