Tetrahydrofuran → 5-(S)-methyl-7-(t-butyldimethylsilyloxy)-2-heptene

HRID 35722

Reaction equation

HRID 35722 reaction equation
O1CC[CH2:3][CH2:2]1.C([Li])CCC.[CH3:11][C@H:12]([CH2:16][CH2:17][O:18][Si:19]([C:22]([CH3:25])([CH3:24])[CH3:23])([CH3:21])[CH3:20])[CH2:13][CH:14]=O>[Br-].C1([P+](C2C=CC=CC=2)(C2C=CC=CC=2)CC)C=CC=CC=1.O>[CH3:11][C@H:12]([CH2:16][CH2:17][O:18][Si:19]([C:22]([CH3:25])([CH3:24])[CH3:23])([CH3:21])[CH3:20])[CH2:13][CH:14]=[CH:2][CH3:3]

Participants

6

Reactant 3

HCID 8028Tetrahydrofuran2×HCID 104438663-(R)-methyl-5-(t-butyldimethylsilyloxy)-1-pentanalHCID 178418339Butyllithium

Product 1

HCID 537803775-(S)-methyl-7-(t-butyldimethylsilyloxy)-2-heptene

Reagents, catalysts & solvents 2

HCID 73727Phosphonium, ethyltriphenyl-, bromide (1:1)CatalystHCID 962WaterSolvent

Procedure

To a slurry of 80 g. (0.2155 m) of triphenyl-ethyl phosphonium bromide in 800 ml. of dry tetrahydrofuran cooled to 0° C. was added 165.7 ml. of 1.3M solution of n-butyl lithium (0.2155 m) in the same solvent. After 2 hours, 45 g. (0.196 m) 3-(R)-methyl-5-(t-butyldimethylsilyloxy)-1-pentanal in 200 ml. of dry tetrahydrofuran was added dropwise to the reaction mixture. The reaction was allowed to stir 2 hours at room temperature and was then poured into water and extracted with ether. The combined extracts were washed with water and a brine solution and dried over magnesium sulfate. Removal of the solvent in vacuo gave a yellow oil which, on distillation gave 37.4 g. of product, b.p. 74°-79° C./0.2-0.1 torr.

Workup

  1. additionwas added 165.7 ml
  2. extractionextracted with ether
  3. washThe combined extracts were washed with water
  4. dry with materiala brine solution and dried over magnesium sulfate
  5. customRemoval of the solvent in vacuo
  6. customgave a yellow oil which
  7. distillationon distillation
  8. customgave 37.4 g

Sources & evidence

ORD record
ord-4c5114fdff2d45a59c871c8312f0440a
Source dataset
uspto-grants-1988_08
Patent number
US04767743

Linked notes

Loading…