2-chloro-1,3,2-benzodioxaphosphole

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of O-phenylene phosphorochloridite (10.12 g, 58 mmol) and pyridine (4.6 g, 58 mmol) in diethyl ether (200 mL) is cooled to 0° C. and treated dropwise with a solution of 4'-chlorophenethyl alcohol (9 g, 57.5 mmol) in diethyl ether (100 mL) and stirred 2 days. The resulting pyridine hydrochloride is collected by filtration and the filtrate is concentrated under vacuum to an oil. A solution of the oil in dichloromethane (150 mL) is stirred 10 days with iodine (14.72 g, 58 mmol) and then the reaction mixture is washed successively with 5% sodium hydroxide solution, 5% sodium bisulfite solution, and then saturated sodium chloride solution. The dried (MgSO4) organic layer is concentrated in vacuo to provide 17.1 g of a pale yellow oil whose proton nuclear magnetic resonance (PMR) spectrum is consistent with its structure. The resulting pyridine hydrochloride is collected by filtration the filtrate is concentrated under vacuum to an oil the reaction mixture is washed successively with 5% sodium hydroxide solution, 5% sodium bisulfite solution The dried (MgSO4) organic layer is concentrated in vacuo