Hexamethylphosphoramide → 1-(4-Bromophenyl)pent-1-ene

HRID 1450028Notes

Reaction equation

[CH2:1]([Li])[CH2:2][CH2:3][CH3:4].CN(C)P(=O)(N(C)C)N(C)C.[Br:17][C:18]1[CH:25]=[CH:24][C:21]([CH:22]=O)=[CH:20][CH:19]=1.[Cl-].[NH4+]>CCCCCC.[Br-].C([P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)CCC.O1CCCC1>[Br:17][C:18]1[CH:25]=[CH:24][C:21]([CH:22]=[CH:1][CH2:2][CH2:3][CH3:4])=[CH:20][CH:19]=1

Participants

Conditions

Temperature: -80 °C

Procedure

52 ml (83.2 mmols) of a 1.6M n-butyllithium solution in hexane are added to a suspension, cooled to -10° C., of 34 g (85.1 mmols) of n-butyltriphenylphosphonium bromide in 150 ml of tetrahydrofuran. After 20 minutes' reaction, the whole is cooled to -80° C. and 50 ml of hexamethylphosphoric triamide are added, as well as 10 g (54 mmols) of 4-bromobenzaldehyde dissolved in 40 ml of tetrahydrofuran. After returning to room temperature and hydrolysis with a saturated ammonium chloride solution, the reaction mixture is extracted with ether. Customary treatment of the organic phase yields 10 g of the expected compound after purification by chromatography on a silica column (eluent: petroleum ether).

Workup

customAfter 20 minutes' reaction
customAfter returning to room temperature
extractionthe reaction mixture is extracted with ether

Sources & evidence

ORD record: ord-9ac130c3904d4173b825e6e76c74d9d9
Source dataset: uspto-grants-1997_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05599975

Reaction notes

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