ChemicalBook CAS DataBase List 11-HENEICOSANOL

11-HENEICOSANOL synthesis

5synthesis methods

Product Name:11-HENEICOSANOL
CAS Number:3381-26-8
Molecular formula:C21H44O
Molecular Weight:312.57

112-29-8 Synthesis

112-29-8
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$6.00/25g

112-44-7
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$15.00/25g

3381-26-8
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$56.89/1g

Yield: 46%

Reaction Conditions:

Stage #1: with iodine;magnesiumBunsen flame;
Stage #2:1-bromo dodecane in tetrahydrofuran at 40; for 2 h;
Stage #3:undecylaldehyde with water;ammonium chloridemore than 3 stages;

Steps:

8
Magnesium turnings (705 mg, 28.9 mmol) and iodine (10 mg, catalytic) were combined and heated over a Bunsen flame under N2 until I2 gas evolved. The flask was allowed to cool, and then dry THF (100 mL) was added. Bromodecane (5.0 mL, 24.1 mmol) was added and the mixture was stirred for 2 h at 40 °C under N2. After this time, undecylic aldehyde (5.0 mL, 24.1 mmol) was added and the reaction was stirred for a further 1 h, at 55 °C, under N2. The reaction was quenched with sat. aq. NH4C1, and the solvent was evaporated under reduced pressure. The residue was diluted with CH2C12 (300 mL) and extracted with aq. NaCl (200 mL) followed by water (200 mL). The organic layer was dried over Na2SO4, filtered, and solvent removed under reduced pressure. The residue was bonded to silica (dissolved in EtOAc and evaporated in the presence of silica) and chromatographed (hexane-DCM 2: 1. TLC; Rf 0.57, Hex-EtOAc 6: 1) to furnish 11-heneicosanol as a white powder (3.44 g, 46%). 1H NMR (300 MHz, CDC13) : No. 3.58 (m, 1 H, OCHR2), 1.26-1. 48 (m, 36 H, 18 x CH2), 0.88 (app t, 6 H, J 6.9 Hz, 2 x CH3) ; 13C NMR (75.5 MHz, CDC13) : 8 72.0 (CH), 37.5, 31.9, 29.7, 29.6, 29.3, 25.7, 22.7 (18 x CH2), 14.1 (2 x CH3) ; LRMS (ESI) m/z 335 [ (M + Na) + 8%] 413 (100) 489 (11).

References:

GRIFFITH UNIVERSITY WO2003/97657, 2003, A1 Location in patent:Page/Page column 27