PROCESS FOR PREPARING LACTAMS Russian patent published in 1997 - IPC

FIELD: original material for synthesis of carbocyclic nucleoside analogues with antitumor activity. SUBSTANCE: preparation of lactams of formula 1 where n is 1 or 2. Reagent 1: cyclopentadiene or cyclohexadiene. Reagent 2: sulfinic acid RSO₂H, where R is (C₁-C₆)-alkyl, phenyl optionally substituted for lower alkyl group or halogen. Reagent 3: chlorocyan. The resulting cycloadduct is subjected to hydrolytic cleavage directly in reaction mixture. Reaction conditions: process is carried out in presence of water. Reagent 2: less than 0.5 mole per mole of reagent 1, pH of reaction mixture is 4-6, temperature ranges from minus 5 to plus 15 C. Reaction mixture comprises organic solvent, acetonitrile, tetrahydrofuran, dioxane, dichloromethine, toluene. Structure of compounds of formula 1: . EFFECT: higher efficiency.