N,O-bis(trimethylsilyl)acetamide → HCID 178445557, compound

Participants

Reaction Steps

(2-Benzyloxycarbonyl-4-methylpentyl)phosphinic acid (1.14 grams, 4.0 mmole), 4-benzylbenzyl bromide (1.31 grams, 5.0 mmole) and N,O-bis(trimethylsilyl) acetamide (2.44 grams, 12 mmole) were combined in dry methylene chloride (40 ml); the mixture was degassed with a stream of dry nitrogen, then stirred at room temperature for 18 hours and refluxed for 24 hours. The cooled solution was quenched with 1N hydrochloric acid (25 ml). The methylene chloride layer was separated and washed with 1N hydrochloric acid (2×25 ml), dried with magnesium sulfate, filtered and concentrated to a turbid oil. This was dissolved in methanol (10 ml)/toluene (40 ml) and treated with excess trimethylsilyldiazomethane (commercial hexane solution). After 30 minutes the excess trimethylsilyldiazo-methane was destroyed with acetic acid. The solution was concentrated to an oil which was chromatographed (75:25--ethyl acetate:hexane) to give 1.18 grams (62%) of 2-[(4-benzylbenzyl)methoxyphosphinoylmethyl]-4-methylpentanoic acid benzyl ester as a colorless oil.

Provenance & Evidence