ChemInform Abstract: Reductive Coupling of Phthalimides with Ketones and Aldehydes by Low‐Valent Titanium: One‐Pot Synthesis of Alkylideneisoindolin‐1‐ones.

Abstract

Synthesis of Alkylideneisoindolin-1-ones. -The title reaction promoted by Zn-TiCl 4 gives two-and four-electron reduced products, (hydroxyalkyl)isoindolinones and alkylideneisoindolinones, selectively in dependance on the reaction conditions used. Alkylideneisoindolinones prepared from phthalimides and aldehydes are obtained as mixtures of geometric isomers. In most cases, the geometric ratios can be increased by treatment with catalytic amounts of pyridinium tosylate. After isomerization, the E-isomers of N-methyl substituted alkylideneisoindolinones and the Z-isomers of N-unsubstituted alkylideneisoindolinones are obtained preferentially [shown only for (VIIIe)]. -(KISE*, N.; KAWANO, Y.; SAKURAI, T.; J. Org. Chem. 78 (2013) 24, 12453-12459, http://dx.