反应详情

252 mg (1.3 mmol) of the isocyanate from example 7 were dissolved at 0° C. in 5 ml of THF and admixed with 109 mg (3.25 mmol, 2.5 eq.) of sodium hydrogencarbonate and 209 mg (1.37 mmol, 1.05 eq.) of 3-azaspiro[5.5]undecane. The mixture was stirred overnight, precipitated salts were removed and the reaction mixture was treated directly with 2.5 ml of 1 M LiOH solution (2.5 mmol, 1.9 eq.). The reaction was monitored by HPLC-MS. When the mass peak of the reactant had disappeared completely, the mixture was acidified cautiously with dilute HCl and the product was isolated by extraction with ethyl acetate, drying of the organic phase over sodium sulfate and concentration under reduced pressure. Yield: 440 mg (quantitative). The crude product was used directly in the amide coupling which follows.

1. customprecipitated salts
2. customwere removed
3. dry with materialdrying of the organic phase over sodium sulfate and concentration under reduced pressure