Nitrogen → (8-(4-Chlorophenylsulfonyl)-9-ethyl-1,4-dioxa-8-azaspiro[4.5]decan-7-yl)methyl dimethylcarbamate

関与物質

反応手順

(8-(4-Chlorophenylsulfonyl)-9-ethyl-1,4-dioxa-8-azaspiro[4.5]decan-7-yl)methanol (111; 1.19 g, 3.18 mmol) and triethylamine (2.21 ml, 15.9 mmol) were added to CH2Cl2 (15 mL) in a flame-dried flask and placed tinder N2. DMAP (77.8 mg, 0.637 mmol) was added and the mixture stirred for 5 minutes. Dimethylcarbamoyl chloride (0.88 mL, 1.54 mmol) was added dropwise and the reaction stirred for 18 hours. The reaction mixture was concentrated under reduced pressure, and equal portions of EtOAc and water were added. The aqueous layer was extracted with several more portions of EtOAc. The combined organic layers were washed with a dilute NaOH solution, 10% citric acid, brine, dried over Na2SO4 and concentrated to yield 940 mg of 112 as a yellow oil. The material was purified by column chromatography using EtOAc/hexanes gradients to yield 836 mg (59%) of a mixture of cis/trans isomers.

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