Sodium Bis(2-methoxyethoxy)aluminum Dihydride (70% in Toluene, ca. 3.6mol/L)

• 3-Phenyl-2-propyn-1-ol [P1147]
• Sodium Bis(2-methoxyethoxy)aluminum Dihydride (70% in Toluene, ca. 3.6 mol/L) [S0467]
• Iodine [I0604]
• Tetrahydrofuran
• Potassium Sodium L-(+)-Tartrate Tetrahydrate (= Rochelle salt) [P1798]
• Sodium Thiosulfate [O0522]

To a reaction vessel tetrahydrofuran (40 mL) was added and cooled with an ice bath. Sodium bis(2-methoxyethoxy)aluminum dihydride (70% in Toluene, ca. 3.6 mol/L) (7.0 mL, 25.0 mmol) and 3-phenyl-2-propyn-1-ol (2.0 g, 15 mmol) diluted in tetrahydrofuran (10 mL) were subsequently added dropwise, and the reaction mixture was stirred at room temperature for 2 hours. The reaction was monitored by TLC and confirmed the starting material was completely consumed, then the reaction mixture cooled in an ice bath. Ethyl acetate (5 mL) was added dropwise to quench and stirred for 30 minutes. The reaction mixture was cooled to -78 °C and iodine (7.5 g, 30 mmol) was added in one portion, then warmed to 0 °C and stirred for 1 hour. The reaction was quenched with respectively saturated aqueous Rochelle salt solution (50 mL)　and saturated aqueous sodium thiosulfate solution (50 mL). The aqueous layer was extracted with ethyl acetate and the organic layer was washed with saturated aqueous sodium thiosulfate solution and brine, then dried over magnesium sulfate and filtered. The filtrate was concentrated to obtain crude product. Purification by silica gel column chromatography (hexane:ethyl acetate = 6:1) gave (Z)-3-Iodo-3-phenyl-2-propen-1-ol　(2.2 g, 56% yield) as a yellow oil.

The reaction mixture was monitored by TLC (hexane:ethyl acetate = 4:1, Rf = 0.6).

¹H NMR (400 MHz, CDCl₃); δ 7.50-7.45 (m, 2H), 7.35-7.27 (m, 3H), 6.26 (t, 1H, J = 5.9 Hz), 4.40 (d, 2H, J = 5.9 Hz), 1.80 (br, 1H).

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