Pyridine → HCID 11335795, compound

Participants

Reaction Steps

90 g of bromine, dissolved in 250 ml of methylene chloride, were added dropwise to a solution of 131 g (0.5 mol) of triphenylphosphine in 500 ml of methylene chloride at 30°-35° C., with exclusion of moisture. The mixture was subsequently stirred at room temperature for 1 hour, a solution of 122 g (0.5 mol) of α-hydroxybenzylphosphonic acid diethyl ester in 250 ml of methylene chloride was then added dropwise at -20° C. in the course of 1 hour, the mixture was subsequently stirred at -20° C. for 1 hour and 40 g of pyridine, dissolved in 250 ml of methylene chloride, were then added dropwise at -20° C. in the course of one hour. The mixture was subsequently stirred for 20 hours, the temperature slowly rising to +20° C. The reaction mixture was transferred to a pear-shaped flask and the solvent was distilled off under a waterpump vacuum. The residue was extracted by stirring with one liter of ether and the undissolved triphenylphosphine oxide was filtered off (120 g of triphenylphosphine oxide=86% of theory). The mother liquor was concentrated in vacuo and the residue was distilled under a high vacuum. 112 g (72% of theory) of α-bromobenzyl-phosphonic acid diethyl ester were obtained as a pale yellow oil with a boiling point of 110° C./0.01 mm Hg and a purity of 95.9% (gas chromatography).

Provenance & Evidence