Iodine → (5R)-2-iodo-6-methyl-7-(2-methylthiazol-4-yl)-5-(triethylsilyloxy)-2,6-heptadiene

HRID 348234

Reaction equation

[CH2:1]([Li])[CH2:2][CH2:3][CH3:4].[I:6]I.C[Si](C)(C)[N-][Si](C)(C)C.[Na+].[CH2:18]([Si:20]([CH2:37][CH3:38])([CH2:35][CH3:36])[O:21][C@@H:22]([C:26]([CH3:34])=[CH:27][C:28]1[N:29]=[C:30]([CH3:33])[S:31][CH:32]=1)CC=O)[CH3:19]>[I-].C([P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)C.C1COCC1.CCCCC>[I:6][C:3](=[CH:2][CH2:1][C@@H:22]([O:21][Si:20]([CH2:37][CH3:38])([CH2:35][CH3:36])[CH2:18][CH3:19])[C:26]([CH3:34])=[CH:27][C:28]1[N:29]=[C:30]([CH3:33])[S:31][CH:32]=1)[CH3:4]

Participants

Conditions

Temperature: -30 °C

Procedure

To a suspension of ethyltriphenylphosphonium iodide (7.90 g), in THF (150 mL) is added n-butyllithium (7.17 mL, 2.5 M in hexane) at ambient temperature. After disappearance of the solid material, the red solution is cannulated into a vigorously stirred solution of iodine (4.54 g) in THF (150 mL) at −78° C. The resulting dark brown suspension is stirred for 5 minutes and allowed to warm gradually to −30° C. A solution of sodium hexamethyldisilazide (17.3 mL, 1.0 M in THF) is added dropwise to afford a dark red solution. A solution of (3R)-3-(triethylsilyloxy)-4-methyl-5-(2-methylthiazol-4-yl)-pent-4-enal (2.0 g) in THF (10 mL) is slowly added, and stirring is continued at −30° C. for 30 minutes. The reaction mixture is diluted with pentane (100 mL), filtered through a pad of Celite, and concentrated. Purification by flash column chromatography on SiO2 (hexane/ethyl acetate, 15:1) affords the vinyl iodide.

Workup

customto afford a dark red solution
stirringstirring
waitis continued at −30° C. for 30 minutes
filtrationfiltered through a pad of Celite
concentrationconcentrated
customPurification by flash column chromatography on SiO2 (hexane/ethyl acetate, 15:1)

Sources & evidence

ORD record: ord-6924a6a04acf4f26b4eaf22e57c69ab9
Source dataset: uspto-grants-2007_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07176235B2

Linked notes

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