Water → HCID 53907000, compound

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Reaction Steps

A solution of 3 g of diethyl malonate in 5 ml of THF was added dropwise into a suspension of 0.05 g of sodium hydride in THF. After the dropwise addition, the mixture was stirred at room temperature for 30 minutes, and a solution of 0.65 g of (R)-1-iodo-3-t-butyldimethylsilyloxybutane in THF was added to the mixture. Then, the mixture was stirred at room temperature overnight, water was added to the mixture, and the majority of THF was removed by distillation. The residue was extracted with ether, and the ether extract was washed with dilute hydrochloric acid and then with water and dried over magnesium sulfate. The solvent was removed by distillation and the residue was subjected to distillation under a reduced pressure to obtain diethyl (R)-3-t-butyldimethylsilyloxybutylmalonate. The obtained compound was dissolved in 10 ml of THF and 2 ml of a 1M solution of tetrabutyl ammonium fluoride in THF was added to the solution, and the mixture was stirred at room temperature overnight and concentrated under a reduced pressure. Water was added to the concentrate and the mixture was extracted with ether. The ether extract was washed with water and dried over magnesium sulfate. Ether was removed by distillation, the residue was dissolved in benzene, p-TsOH was added to the solution and the mixture was refluxed for 5 hours. The reacted solution was washed with an aqueous solution of sodium hydrogen carbonate and dried, the solvent was removed by distillation, and the residue was purified by the silica gel column chromatography to obtain (2RS,5R)-2-ethoxycarbonyl-5-methyl-δ-valerolactone. The obtained compound was reduced with sodium borohydride to obtain (2RS,5R)-2-hydroxymethyl-5-methyl-δ-valerolactone. In the same manner as described in Example 1, the obtained compound was reacted with 4-(4'-octyloxy)biphenol by using triphenylphosphine and diethyl azodicarboxylate. The reacted solution was purified by the silica gel column chromatography to obtain (2RS,5R)-2-(4'-octyloxybiphenyl)oxymethyl-5-methyl-δ-valerolactone. The obtained product was further fractionated and purified by HPLC to obtain (2R,5R)-2-(4'-octyloxybiphenyl)oxymethyl-5-methyl-δ-valerolactone and (2S,5R)-2-(4'-octyloxybiphenyl)-oxymethyl-5-methyl-δ-valerolactone. They showed the following phase transitions. ##STR39##

Provenance & Evidence