Phenyl phosphorus dichloride → HCID 178419207, compound

Participants

Reaction Steps

To a solution of 12.5 g (47.7 mmol) 1-Iodo-2-methoxy-3,5-dimethylbenzene in 150 ml dry THF are added under a nitrogen atmosphere 47.7 ml of a 1.0 M solution of isopropylmagnesiumchloride.LiCl in THF at −78° C. The Grignard solution is allowed to warm to room temperature (2 h) and then added via a dropping funnel to a cooled (−78° C.) solution of 8.1 g (45 mmol) PhPCl2 in 100 ml dry THF over a period of ca. 1 h. The solution is allowed to warm to room temperature and stirred for 3 h (a colour change to orange is observed during this time). The reaction mixture is then treated with 20 ml of a 3.0 M solution of MeMgCl in THF (60 mmol) and stirred at room temperature for 1 h (orange colour disappears). Borane-THF complex (1.0 M in THF, 75 ml) is then added and the solution left stirring overnight. The reaction is then carefully quenched with water (100 ml), the organic layer separated and the aqueous layer extracted with CH2Cl2 (2×100 ml). The combined organic layers are washed with brine (2×200 ml), dried over Na2SO4, filtered and evaporated to dryness in vacuo. The oily crude product is purified on a silica column (30×5 cm, eluent cyclohexane: EtOAc—4:1) to yield 3.6 g (13.2 mmol, 29%) of pure racemic product.

Provenance & Evidence