Hydrochloric Acid → (R)-4-[2-(4-Heptyloxy-phenyl)-ethyl]-4-methyl-2-oxo-[1,2,3]oxathiazolidine-3-carboxylic acid tert-butyl ester

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Reaction Conditions

Reaction Steps

A stirred solution of thionyl chloride (0.14 ml, 1.91 mMol) in acetonitril (10 ml) is cooled to −40° C. At this temperature, a solution of [(R)-3-(4-heptyloxy-phenyl)-1-hydroxymethyl-1-methyl-propyl]-carbamic acid tert-butyl ester (300 mg, 0.76 mMol) in acetonitril (5 ml), and pyridine (0.31 ml, 3.81 mMol) are added successively. The mixture is allowed to warm to −10° C. over 2.5 hours. The reaction mixture is then poured onto a biphasic mixture of AcOEt and HCl (aqueous, 1 M). The aqueous phase is extracted twice with AcOEt. The combined organic layers are washed with NaHCO3 (saturated aqueous solution), dried (Na2SO4) and concentrated under reduced pressure. Column chromatography eluting with 5%→15% AcOEt in heptane gives the title compounds as colourless oils (2 diastereomers, dr=1:1).

Provenance & Evidence