Chemical Properties
colourless to yellow liquid or solid
Uses
1-Bromohexadecane has been used:
in the preparation of soluble carbon nano-onions by covalent functionalization with hexadecyl chains
as extraction solvent in determination of endocrine-disrupting phenols (EDPs) in water samples by ultrasound-assisted emulsification microextraction (MS-USAEME) method
in the preparation of [2-(methacryloyloxy)ethyl]dimethylhexadecylammonium bromide monomer, required for the synthesis of novel methacrylate based adsorbents
in the synthesis of surfactant, N-hexadecyl ethylenediamine triacetic acid (HED3A)
Uses
1-Bromohexadecane is used in the preparation of soluble carbon nano-onions by covalent functionalization with hexadecyl chains. It is also used to synthesize [2-(methacryloyloxy)ethyl]dimethylhexadecylammonium bromide monomer, required for the synthesis of novel methacrylate based adsorbents.
Preparation
Synthesis of 1-Bromohexadecane from hexadecanol by bromination: put hexadecanol into the reaction pot and stir, heat, melt and put in red phosphorus. Add bromine drop by drop at 100℃ with sufficient stirring on one side, control 120-130℃, about 6h drop by drop, continue the reaction and drain the hydrogen bromide. Cool to below 50 ℃, add saturated and sodium chloride, stirring and washing, resting stratification, parting off the lower waste stream, then wash with water to neutral, distillation, collect 220-230 ℃ (2kPa) fraction, to obtain 1-bromohexadecane.
Synthesis
General procedure for the synthesis of bromohexadecane from 1-hexadecanol: ethyl α,α-diacetoacetate (2a, 0.41 mmol, 1.2 eq.), 1-hexadecanol (1a, 0.34 mmol, 1.0 eq.), and triphenylphosphine (Ph3P, 0.68 mmol, 2.0 eq.) were added to 3 mL of dichloroethane (DCE) at room temperature. The reaction was carried out in air. The reaction mixture was stirred at room temperature and the reaction progress was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction was quenched by the addition of 3 mL of water, followed by extraction with ethyl acetate (3 x 3 mL). The organic layers were combined, washed with saturated saline, dried over anhydrous sodium sulfate (Na2SO4) and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography with the eluent being petroleum ether or a solvent mixture of petroleum ether and ethyl acetate to give the target product hexadecyl bromide (3a).
Purification Methods
Shake the bromide with H2SO4, wash with H2O, dry with K2CO3 and fractionally distil it in vacuo.[Beilstein 1 IV 542.]
References
[1] Tetrahedron Letters, 2014, vol. 55, # 1, p. 90 - 93
[2] Chemistry and Physics of Lipids, 1993, vol. 66, # 3, p. 161 - 170
[3] JAOCS, Journal of the American Oil Chemists' Society, 1996, vol. 73, # 7, p. 847 - 850
[4] Journal of the American Pharmaceutical Association (1912-1977), vol. 38, p. 288
[5] Chem.Abstr., 1949, p. 8610
