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

Participants

Reaction Conditions

Reaction Steps

HATU (0.316 g) was added in one portion to a solution at 0° C. of 9-(3-(2-(tert-butyldimethylsilyloxy)ethyl)-2-fluorobenzyl)-1-oxa-4,9-diazaspiro[5.5]undecane (example 78, step d) (0.271 g) and 5-ethylthiophene-3-carboxylic acid (0.1 g) and triethylamine (0.36 mL) in DMF (10 mL). The mixture was then stirred at 20° C. for 1 hour. The reaction mixture was partitioned between ethyl acetate and brine, the organic layer was washed twice with brine, dried over sodium sulphate, filtered and the solvent evaporated under reduced pressure. The residue was dissolved in THF (20 mL) and treated with tetrabutylammonium fluoride (1M in THF, 1.921 mL). The reaction mixture was allowed to stand at 20° C. for 18 hours and the solvent was then removed under reduced pressure. The crude product was purified by flash silica chromatography using 2% methanol in dichloromethane with 1% triethylamine as solvent. Pure fractions were evaporated to dryness to afford the subtitled compound. Yield 0.12 g.

Provenance & Evidence