Addition of Metalated 3‐Alkyl‐Substituted Alkoxyallenes to Imines: Preparation of Tetrasubstituted 2,5‐Dihydropyrroles, Pyrrolidin‐3‐ones, and Pyrroles

Abstract

The study of four different salts of a hybrid glycinepolyoxotungstate has revealed photocoloration that is dependent on the intramolecular hydrogen bonding between glycine ligand ammonium groups and the polyoxotungstate. Four compounds comprised of the hybrid polyoxometalate [As 4 {W 3 Y}W 44 Y 4 O 159 (Gly) 8 (H 2 O) 12 ] 9-(Gly = glycine) with glycinium, benzylammonium, 4-methylbenzylammonium, or benzyltriethylammonium countercations have been synthesized and structurally characterized. In the solid state, two of the com- [a]

Metal-mediated synthesis of pyrrolines

“…Reissig et al published the synthesis of 1,2,3,5-tetrasubstituted 3-pyrrolines 437 from a mixture of pro-cis and pro-trans allenylamines (435 and 436) using silver nitrate as catalyst at room temperature (Scheme 137). 198 The cis and trans 3-pyrrolines (cis-437 and trans-437) were obtained in good yields. However, the silver-catalyzed cyclization was not stereoespecic since silver nitrate would allow a congurational isomerization of axially chiral allenylamines 435 and 436.…”