Tetrakis(hydroxymethyl)phosphonium chloride → 2,2-Dimethoxyethylcyclopent-3-enol

Beteiligte Stoffe

Reaktionsschritte

A solution of 4-(2,2-dimethoxyethyl)hepta-1,6-dien-4-ol (28 g, 140 mmol) in DCM (2 L) was charged to a 3 L RB flask. Dry argon was bubbled through the solution for ˜30 minutes. Grubbs second generation catalyst (5.9 g, 7.0 mmol) was added and the reaction was allowed to stir under argon for 15 hours. The reaction was quenched with a solution of tetrakis-(hydroxymethyl)phosphonium chloride (27 g, 140 mmol) in isopropanol (200 mL) and 10 N NaOH (14 mL), and stirred for 15 hours. The reaction was diluted with water (1 L) and poured into a seperatory funnel. The DCM layer was separated and the aqueous was extracted with DCM (3×100 mL). The combined organics were concentrated to a dark oil which was purified by flash chromatography on a 330 g ISCO column eluting by gradient hexanes to 20% EtOAc/hexanes over a 50 minute period. Product fractions were combined to afford the title compound.

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