Tetrabutylammonium Fluoride → (9-((5-(2-Hydroxyethyl)thiophen-3-yl)methyl)-1-oxa-4,9-diazaspiro[5.5]undecan-4-yl)(2-isopropylthiazol-4-yl)methanone

Participants

Reaction Steps

Tetrabutylammonium fluoride (1M in tetrahydrofuran, 2.1 mL) was added to a solution of (9-((5-(2-(tert-butyldimethylsilyloxy)ethyl)thiophen-3-yl)methyl)-1-oxa-4,9-diazaspiro[5.5]undecan-4-yl)(2-isopropylthiazol-4-yl)methanone (example 278, step d) (0.80 g) in tetrahydrofuran (10 mL). After 2 h, the solution was evaporated in vacuo and the residue partitioned between saturated sodium bicarbonate solution (50 mL) and ethyl acetate (50 mL). The layers were separated and the aqueous phase extracted with ethyl acetate (2×50 mL). The combined organic solutions were washed with brine (50 mL), dried over sodium sulphate, filtered and evaporated. The residue was purified by silica gel chromatography, eluting with 20:1 ethyl acetate:triethylamine. The fractions containing product were combined and evaporated in vacuo to give the subtitled compound as a gum. Yield 0.61 g.

Provenance & Evidence