Chlorotrimethylsilane → Lithium diisopropylamide

HRID 1732250Notes

Reaction equation

HRID 1732250 reaction equation
C([Li:5])CCC.[CH:6]([NH:9][CH:10]([CH3:12])[CH3:11])([CH3:8])[CH3:7].[CH2:13]([O:20][CH2:21][CH:22]([CH3:34])[CH2:23][CH2:24][CH2:25][C:26]([CH3:33])=[CH:27][CH2:28][CH2:29][C:30](=[O:32])[CH3:31])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[CH3:35][Si:36](Cl)([CH3:38])[CH3:37].C(=O)(O)[O-].[Na+]>CCCCCC.O1CCCC1.C(N(CC)CC)C>[CH:6]([N-:9][CH:10]([CH3:12])[CH3:11])([CH3:8])[CH3:7].[Li+:5].[CH2:13]([O:20][CH2:21][CH:22]([CH3:34])[CH2:23][CH2:24][CH2:25][C:26]([CH3:33])=[CH:27][CH2:28][CH2:29][C:30]([O:32][Si:36]([CH3:38])([CH3:37])[CH3:35])=[CH2:31])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1

Participants

10

Reactant 5

HCID 6397ChlorotrimethylsilaneHCID 7912DiisopropylamineHCID 516892Sodium Bicarbonate2×HCID 53793676HCID 53793676, compoundHCID 178418339Butyllithium

Product 2

HCID 2724682Lithium diisopropylamideHCID 54158718HCID 54158718, compound

Reagents, catalysts & solvents 3

HCID 8028TetrahydrofuranSolvent3×HCID 8058HexaneSolventHCID 8471TriethylamineSolvent

Conditions

Temperature
-70 °C

Procedure

Lithium diisopropylamide was prepared by the addition of 2.1 M n-butyllithium in hexane (22.7 ml, 48.8 mM) to diisopropylamine (3.45 ml, 48.8 mM) in dry tetrahydrofuran (125 ml). The base is cooled to -70° C., 1-benzyloxy-2,6-dimethyl-10-oxo-undec-6-ene (12.4 g, 41 mM) in dry tetrahydrofuran (300 ml) is added and the mixture is allowed to stir for 1 hour. Trimethylsilyl chloride (14 ml, 111 mM) is added to triethylamine (3.7 ml, 26.8 mM) in dry tetrahydrofuran (50 ml). The mixture is centrifuged, and the supernatant is added to the lithio salt at -70° C. After 4 hours, sodium bicarbonate (2.5 g) and saturated sodium bicarbonate (250 ml) are added, the reaction mixture is partitioned between ether and brine, the aqueous phase is extracted with ether and the combined extracts are washed with brine and dried (Na2SO4). The solvent is removed in vacuo to give crude 11-benzyloxy-6,10-dimethyl-2-trimethylsiloxy-undec-1,5-diene.

Workup

  1. waitAfter 4 hours
  2. customthe reaction mixture is partitioned between ether and brine
  3. extractionthe aqueous phase is extracted with ether
  4. washthe combined extracts are washed with brine
  5. dry with materialdried (Na2SO4)
  6. customThe solvent is removed in vacuo

Sources & evidence

ORD record
ord-926dfb6d5f144996b416ef88b9901878
Source dataset
uspto-grants-1980_12
Patent number
US04237055

Reaction notes

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