(3R)-3-Amino-3-[3-[4-(5-ethoxy-2-fluoro-phenyl)-6-methyl-pyrimidin-2-yl]prop-2-ynyl]-1-methyl-pyrrolidin-2-one → (5R)-2-[4-(5-ethoxy-2-fluoro-phenyl)-6-methyl-pyrimidin-2-yl]-7-methyl-1,7-diazaspiro[4.4]non-1-en-6-one

Participants

Reaction Conditions

Reaction Steps

Silver trifluoromethanesulphonate (60.06 mg, 0.23 mmol) was added to a solution of (3R)-3-amino-3-[3-[4-(5-ethoxy-2-fluoro-phenyl)-6-methyl-pyrimidin-2-yl]prop-2-ynyl]-1-methyl-pyrrolidin-2-one (which may be prepared as described in Description 19) (447 mg, 1.17 mmol) in MeCN (20 mL) at 20° C. and the reaction was stirred for 66 hrs. An additional 10 mol % AgOTf was added, stirring was continued for an additional 3 days then the mixture was heated to 40° C. until no starting material remained. The solvent was evaporated and the residue was partitioned between water and EtOAc. The organic layer was dried (Na2SO4) and the solvent was evaporated to afford a brown oil. This was purified using a Biotage Isolera with a 25 g SNAP cartridge, eluting with a 0 to 50% mixture (9% MeOH; 89% EtOAc and 2% 880 NH3) in EtOAc affording the (5R)-2-[4-(5-ethoxy-2-fluoro-phenyl)-6-methyl-pyrimidin-2-yl]-7-methyl-1,7-diazaspiro[4.4]non-1-en-6-one (D20) (335 mg, 0.876 mmol, 74.9% yield) as a light brown solid.

Provenance & Evidence