3,5-Dimethoxybenzyl bromide

3,5-DIMETHOXYBENZYL BROMIDE is White Solid

General procedure: benzyl alcohols (1 mmol) in dry benzene (15 mL) and phosphorus tribromides (0.5 mL) and stirred at room temperature to get respective benzyl bromides in quantitative yields, usual work-up.To a solution of 3, 5-dimethoxybenzylalcohol (1.5g, 8.918 mmol) in diethyl ether (45mL) under argon atmosphere was added pyridine (0.034mL, 0.445 mmol). Subsequently, phosphorous tribromide (0.83mL, 8.918 mmol) was added dropwise and the resulting reaction mixture was warmed to 35°C and stirred at that temperature for 3h. The reaction mixture was quenched with slow addition of ice-cold water and diluted with ethyl acetate. The aqueous layer was separated and extracted with ethyl acetate (3x30mL). The organic phase was washed with brine, dried over NaPBrPBr3 (3.10 mL) was addeddrop wise to a solution of (4) 9 g (53.545 mmol) in diethylether at 0 °C. The mixture was stirred at 0 °C for 30 min, and after completion of the reaction (monitored by TLC), the reaction mixture was quenched by slow addition ofpotassium bromide solution, extracted with diethyl ether, washed with brine, dried over Na2SO4 and concentrated toprovide the product (5).1-(Bromomethyl)-3, 5-dimethoxybenzene (5) White solid;Yield: 97 percent; mp 68–70 °C;1H NMR (CDCl3, 400 MHz): δ 6.55–6.53 (2H, m, H–2, H–6), 6.40–6.38 (1H, m, H–4), 4.42 (2H, s, –CH2–Br), 3.79 (6H, s, 2 X O–CH3); 13C NMR(CDCl3, 75 MHz): δ 161.1 (C, C–3, C–5), 139.7 (C, C–1), 106.1 (CH, C–2, C–6), 98.2 (CH, C–4), 55.5 (O–CH3), 30.5(H2C–Br); for C9H11BrO2 MS (ESI) (m/z) 230 [M + H]+.NaBHPhosphorus tribromide (0.4 eq) was added to the alcohol 304 (25 g, 0.13 mol) in THF (100 mL) very slowly at -10° C. and the mixture which resulted was stirred for 15-30 min at the same temperature. In an ice bath and argon, Was dissolved in 20mL of dry CH2Cl2 4.088g (0.024mol) 3, 5- dimethoxybenzene in 100mL methanol 3 neck round bottom flask, Slowly by syringe while stirring was dissolved in 10mL of dichloromethane was added dropwise a solution of 2.54mLPBr3, After 2h the reaction into an ice bath at room temperature, The reaction was continued 2-3h, TLC tracking and detection, The completion of the reaction, etc. The reaction solution was poured into ice water 50mL, Stirring, Lower for the milky white liquid, Plus sodium bicarbonate adjusted to pH 7, After separation of the aqueous layer was extracted with ethyl acetate, Dried over anhydrous sodium sulfate, The solvent was distilled off under reduced pressure, Dried to give compound 4The yield was 85.4percent, To a dry 250 mL rbf charged with 125 mL dry CH2Cl2 cooled to 0 °C was added in order, PPh3 (7.59 g, 28.9 mmol, 1.2 eq.), imidazole (1.97 g, 28.9 mmol, 1.2 eq.), Br2 (1.50 mL, 28.9 mmol, 1.2 eq.) and 3, 5-dimethoxybenzyl alcohol (4.06 g, 24.1 mmol, 1.0 eq.). The reaction was stirred at r.t. for 24 h. Workup provided 3, 5-dimethoxybenzyl bromide (4.35 g, 78percent) as a colourless oil.

3,5-Dimethoxybenzyl bromide may be used in various organic synthesis such as 3,4,3′,5′-tetramethoxystilbene; 3,5-dimethoxyphenylacetic acid; 1-(3,5-dimethoxyphenyl)-4-pentene etc., and 3,5-Dimethoxybenzyl bromide may be used as starting material in the multi-step synthesis of resveratroland 3,5-dimethoxyhomophthalic acid.
3,5-DIMETHOXYBENZYL BROMIDE is used in dimethoxybenzene alkyl addition.

Molecular Weight:231.09
XLogP3:2.4
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:3
Exact Mass:229.99424
Monoisotopic Mass:229.99424
Topological Polar Surface Area:18.5
Heavy Atom Count:12
Complexity:118
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes