Allyl bromide → 3-(Allyloxy)-4-methylpent-1-yne

Beteiligte Stoffe

Reaktionsschritte

A solution of 4-methylpent-1-yn-3-ol (2.00 g, 20.38 mmol) in DMF (30 ml) was cooled (0° C. ice bath) and treated with 60% NaH (0.992 g, 24.80 mmol). The reaction was stirred for 20 min, then warmed to room temperature and stirred for 1 hr. To this was added allyl bromide (5.3 ml, 61.2 mmol) over 5 min. The reaction was stirred over the weekend. The reaction was diluted with Et2O (100 mL), washed with water (4×25 mL), brine (25 mL), dried (MgSO4), filtered and concentrated to give the product, 3-(allyloxy)-4-methylpent-1-yne (2.401 g, 13.03 mmol, 63.9% yield) as a pale yellow mobile oil. 1H NMR consistent with expected product; contains approx 4:1 product/SM. Used as-is without further purification. 1H NMR (CDCl3) δ: 5.86-5.99 (m, 1H), 5.32 (dq, J=17.2, 1.7 Hz, 1H), 5.16-5.25 (m, 1H), 4.28 (ddt, J=12.7, 5.0, 1.6 Hz, 1H), 4.19 (td, J=5.7, 2.1 Hz, 1H), 3.98 (ddt, J=12.7, 6.3, 1.3 Hz, 1H), 3.87 (dd, J=5.8, 2.0 Hz, 1H), 2.41 (d, J=2.0 Hz, 1H), 1.92-2.03 (m, 1H), 0.98-1.06 (m, 8H).

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