Synthesis of decahydropyrrolo[2,1,5-cd]indolizine derivatives through RuCl3/AgOTf induced alkene–alkene and alkene–arene double cycloisomerizations

Molecular diversity of the three-component reaction of α-amino acids, dialkyl acetylenedicarboxylates and N-substituted maleimides

The one-pot three-component reaction of secondary α-amino acids with dialkyl acetylenedicarboxylate and N-substituted maleimides afforded functionalized pyrrolo[3,4-a]pyrrolizines, pyrrolo[3′,4′:3,4]pyrrolo[1,2-c]thiazoles, pyrrolo[3,4-a]indolizines and octahydropyrrolo[3,4-c]pyrroles.

Highly efficient and diastereoselective synthesis of new pyrazolylpyrrolizine and pyrazolylpyrrolidine derivates by a three-component domino process

Diastereoselective reactions between 4-formylpyrazoles, N-substituted maleimides and glycine derivates led to new series of pyrazolyldipyrrolo [3,4-a:3',4'-f]pyrrolizines and pyrazolylpyrrolo[3,4-c]pyrroles in good yields. The reactions proceeded by a domino process through azomethine ylides formed in situ via a 1,3-dipolar cycloaddition reaction.

Synthesis of functionalized indolizidines through Pauson-Khand cycloaddition of 2-allylpyrrolidines

A concise entry to functionalized indolizidine scaffolds through a domino 2-aza-Cope-[3 + 2] dipolar cycloaddition and Pauson-Khand [2 + 2 + 1] cyclization has been accomplished. The process was conducted under mild conditions to afford diverse indolizidine systems as single diastereomers in good overall yields.

Methyl (3aRS,3cRS,6cSR,7RS,8RS,8aSR)-2,5-bis(4-chlorophenyl)-7,9-bis(1,3-diphenyl-1H-pyrazol-4-yl)-1,3,4,6-tetraoxododecahydro-1H-dipyrrolo[3,4-a:3',4'-f]pyrrolizine-3b-carboxylate dimethylformamide disolvate: a three-dimensional hydrogen-bonded framework

The racemic title dipyrrolopyrrolizine compound crystallizes from dimethylformamide as a disolvate, C(55)H(39)Cl(2)N(7)O(6)·2C(3)H(7)NO. None of the four fused heterocyclic rings is planar; one adopts an envelope conformation, two others adopt half-chair conformations and the fourth adopts a conformation intermediate between an envelope and a half-chair. The arrangement of the ring fusions is such as to preclude the possibility of internal mirror symmetry. The three independent molecular components are weakly linked by C-H···O hydrogen bonds, and the dipyrrolopyrrolizine molecules are linked by a combination of four C-H···O and one C-H···π(arene) hydrogen bond to form a three-dimensional framework, from which the dimethylformamide solvent molecules are pendent. However, aromatic π-π stacking interactions are absent in the structure.