Triethylamine → (9-(3-(2-Hydroxyethyl)benzyl)-1-oxa-4,9-diazaspiro[5.5]undecan-4-yl)(5-isopropylthiophen-3-yl)methanone

Beteiligte Stoffe

Reaktionsschritte

O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (0.55 g) was added to a solution of 2-(3-(1-oxa-4,9-diazaspiro[5.5]undecan-9-ylmethyl)phenyl)ethanol (example 82, step a) (0.32 g), 5-isopropylthiophene-3-carboxylic acid (0.19 g) and triethylamine (0.61 mL) in DMF (7 mL) at 0° C. The resulting yellow solution was allowed to warm to RT and was stirred for 2 h. The mixture was partitioned between ethyl acetate (100 mL) and brine (100 mL), the organic phase was washed with brine (2×100 mL), dried over sodium sulphate, filtered and the solvent evaporated. The resulting gum was purified by silica gel chromatography eluting with 47.5:47.5:5 isohexane:ethyl acetate:triethylamine to 95:5 ethyl acetate:triethylamine gradient. The fractions containing product were combined, toluene (200 mL) was added, and the solvent evaporated under reduced pressure to give the subtitled compound as a clear gum. Yield 0.4 g.

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