* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
copper(l) chloride; In tetrahydrofuran; petrol ether; benzene;
EXAMPLE 20 1,1,18,18-tetra(carboethoxy)-2,2,17,17-tetramethyloctadecane The procedure of Example 1 was followed except that the bis-Grignard reagent was prepared from 3.0 g of <strong>[37688-96-3]1,14-dibromotetradecane</strong> and 0.75 g of Mg turnings in 40 ml of dry THF. The bis-Grignard reagent was then added dropwise to a stirred suspension of 0.031 g CuCl and 3.72 g of diethyl isopropylidenemalonate in 15 ml of dry THF. The addition product was protonated and extracted into ether as in Example 1 followed by silicic acid (400 mesh) chromatography in benzene:petrol ether 1:2.5 to yield the title compound. 86% yield. NMR (CDCl3): 4.3 (q, 8H); 3.5 (s, 2H); 1.5 (m, 40H); 1.1 (m, 12H).