REACTIONS OF 5-SUBSTITUTED (S)-1-ACYL-3-[(E)-(DIMETHYLAMINO)-METHYLIDENE]PYRROLIDINE-2-ONES AND (S)-3-[(E)-(DIMETHYL-AMINO)METHYLIDENE]TETRAHYDROFURAN-2-ONES WITH AMINES. PREPARATION OF INTERMEDIATES IN THE ‘RING SWITCHING’ SYNTHESIS OF HETEROARYLALANINE- AND HETEROARYLLACTIC ACID DERIVATIVES AND THEIR ANALOGS

Marko Škof, Jurij Svete, Branko Stanovnik
Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
Simona Goliè-Grdadolnik
National Institute of Chemistry, Ljubljana, Slovenia
 

Abstract

5-Substituted (S)-1-acyl-3-[(E)-(dimethylamino)methylidene]pyrrolidin-2-ones 1–3 and (S)-3-[(E)-(dimethylamino)methylidene]-5-(methoxycarbonyl)tetrahydrofuran-2-one 4, chiral cyclic analogs of 2-substituted alkyl 3-(dimethylamino)propenoates, were treated with alkyl, aryl, and heteroarylamines 6–25 under mild conditions to give 5-substituted (S)-3-[(substituted amino)methylidene]pyrrolidin-2-ones 26–47 and (S)-3-[(E)-(substituted amino)methylidene]-tetrahydrofuran-2-ones 48–52 as intermediates in a ‘ring switcing’ synthesis of 3-heteroarylalanine- and 3-heteroaryllactic acid derivatives and their analogs.