Benzenemethanol, 3-(2-propen-1-yl)- synthesis

Yield:-

Reaction Conditions:

Stage #1: 3-allyl-benzoic acid ethyl esterwith diisobutylaluminium hydride in dichloromethane at 0; for 1 h;
Stage #2: with methanol in dichloromethane;

Steps:

F3.a

To a solution of 8.42 g (39.3 mmol) 3-allyl-benzoic acid ethyl ester (J. Med. Chem. 2004, 47, 5937) in 150 ml DCM stirred at 0° C. are added dropwise 100 ml diisobutylaluminium hydride (1 M solution in DCM). Stirring is continued at this temperature for 1 h before the reaction is quenched via careful addition of 20 ml methanol. The mixture is stirred at room temperature and 100 ml of a 1 M sulfuric acid is added. After 1 hour the aqueous phase is extracted twice with DCM and the combined organic layers are washed with water, dried over Na₂SO₄ and chromatographed on silica gel (EtOAc/hexanes 1:4) to give 4.53 g colorless oil.Rf: (Hexane/EtOAc=20/1): 0.71¹H-NMR (400 MHz, CDCl₃): 7.36-7.15 (m, 4H), 6.07-5.96 (m, 1H), 5.17-5.08 (m, 2H), 4.69 (s, 2H), 3.42 (d, 2H).LC (Nucleosil C-18HD, 4×70 mm, 3 μm, 20-100% MeCN (6 min), 100% MeCN (1.5 min)): 3.943 min.MS (ES+): 131=[M-OH]⁺

References:

US2008/132477,2008,A1 Location in patent:Page/Page column 52