Synthesis
General procedure for the synthesis of 5-carboxypentyltriphenylphosphonium bromide from 6-bromohexanoic acid and triphenylphosphine: 6-bromohexanoic acid (10.00 g, 51.27 mmol) and triphenylphosphonium (14.12 g, 53.83 mmol) were dissolved in freshly distilled acetonitrile (50 mL) and the reaction mixture refluxed for 48 h under vigorous stirring. Upon completion of the reaction, the solution was cooled to room temperature and precipitation of Wittig salt was induced by scraping the inner wall of the glass reactor. The resulting white solid product was collected by filtration and washed with ether to give the final 5-carboxypentyltriphenylphosphonium bromide in 98% (22.87 g) yield. The structure of the product was confirmed by 1H NMR (400 MHz, CD3OD): δ 1.62-1.72 (m, 6H), 2.29 (t, 2H), 3.40-3.47 (m, 2H), 7.76-7.91 (m, 15H).
References
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[2] Analytical Chemistry, 2006, vol. 78, # 1, p. 71 - 81
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[4] Journal of Natural Products, 2001, vol. 64, # 11, p. 1426 - 1429
[5] Patent: WO2008/30532, 2008, A2. Location in patent: Page/Page column 41
