1P12: j) Sequential aldol condensation for the synthesis of new glycine antagonists

S. A. Giacobbe et al.⁴⁴ synthesized a new glycine antagonist via sequential aldol condensation-lactonization-elimination reaction using aldol condensation, a key step as shown in scheme 12. In his attempt, the Li enolate of N-phenylpyrrolidone, prepared by treatment of 50 with a stoichiometric amount of t-BuLi for 1.5 h was reacted with 49 in THF at -78 °C. Resulting in a 3/2 mixture of aldol products 51a (Z-form) and 51b (E-form) in 60% cumulative yield.

______________
44. S. A. Giacobbe, D. Baraldi, and R. Di Fatrio,  Bioorg. Med. Chem. Lett., 1998, 8, 1689.
Next Page