methyl 2,2-dimethyl-3-(tetrahydro-2H-pyran-2-yloxy)propanoate synthesis

Yield:1218915-52-6 100%

Reaction Conditions:

sulfuric acid on silica gel in dichloromethane at 0 - 20;

Steps:

A.1

Step 1: Synthesis of 2,2-Dimethyl-3-(tetrahydro-pyran-2-yloxy)-propionic acid methyl ester To a solution of 66.3 mL (0.51 mol) of hydroxypivalic acid methyl ester in DCM (325 mL) are added 95.8 mL (1.04 mol) of 3,4-dihydro-2H-pyran. The reaction mixture is cooled to 0° C. and sulfuric acid on silica gel (2.04 g, 0.2 mL sulfuric acid/10 g silica gel) is added and the reaction mixture is stirred at room temperature for 25 minutes. After this time, the reaction mixture is filtered and concentrated under reduced pressure to yield 129 g of 2,2-dimethyl-3-(tetrahydro-pyran-2-yloxy)-propionic acid methyl ester as a yellow oil, which is used in the next step without further purification. Yield: quantitative; ¹H NMR (400 MHz, DMSO-d6) δ ppm 1.12 (6H, s), 1.13 (6H, s), 1.4-1.7 (6H, m), 3.3 (1H, m), 3.4 (1H, m), 3.6 (3H, s), 3.65 (1H, d), 3.7 (1H, m), 4.55 (1H, t).

References:

US2010/76029,2010,A1 Location in patent:Page/Page column 45