2-Allyl-2-Methyl-1,3-propanediol synthesis

Yield:25462-37-7 90%

Reaction Conditions:

with lithium aluminium tetrahydride in diethyl ether at 0 - 20; for 12 h;

Steps:

3 4.10.3 2-Allyl-2-methylpropane-1,3-diol 3

To a solution of LAH (2.7 g, 71.14 mmol,) in dry ether (150 mL) a solution of diethyl 2-allyl-2-methylmalonate (10 g, 46.67 mmol) in dry ether (100 mL) at 0 °C was added via a cannula.
The reaction was then allowed to warm up to rt and stirred for 12 h. TLC analysis indicated the disappearance of the starting material and the reaction was quenched by the dropwise addition of a saturated Na₂SO₄ solution.
The precipitated white aluminum salt was filtered off and the aluminum salt was washed thoroughly with ether (3 * 100 mL).
The filtrate was washed with satd aq NaCl (50 mL), dried over Na₂SO₄, and concentrated in vacuo.
The crude residue was purified by flash column chromatography (EtOAc/hexane, 1:3) to afford compound 3 (5.46 g) in 90% yield. R_f = 0.2 (EtOAc/hexane, 1:3). ¹H NMR (200MHz, CDCl₃), δ_H: 5.92-5.71 (m, 1H), 5.11 (d, 1H, J=1.4Hz), 5.09-5.01 (m, 1H), 3.45 (s, 4H), 2.85 (br s, 2H), 2.08 (d, 2H, J=7.6Hz), 0.81 (s, 3H). ¹³C NMR (50MHz, CDCl₃), δ_C: 134.3, 118.0, 69.9, 39.4, 38.8, 18.6. HRMS (ESI) for C₇H₁₄O₂Na [M+Na]⁺, calculated: 153.0892; found: 153.0897.

References:

Kumar, Rajan;Rej, Rohan Kalyan;Halder, Joydev;Mandal, Haridas;Nanda, Samik [Tetrahedron Asymmetry,2016,vol. 27,# 11-12,p. 498 - 512]