A facile and efficient synthetic protocol was established for the construction of novel tri- and tetra-cyclic pyrrolo/pyrrolizinoquinoline architectures via the in situ formation of azomethine ylide followed by an intramolecular [3 + 2] cycloaddition reaction strategy. This protocol leads to the creation of two/three new rings and three/four contiguous stereocentres, in which one of them is a t...

The title compound, C14H12FN3O, adopts an E conformation with respect to the azomethine bond. The pyridyl and fluoro-benzene rings make dihedral angles of 38.58 (6) and 41.61 (5)° respectively with the central C(=O)N2CC unit, resulting in a non-planar mol-ecule. The inter-molecular inter-actions comprise two classical N-H⋯O and N-H⋯N hydrogen bonds and four non-classical C-H⋯O and C-H⋯F hydroge...

In the title compound, C(15)H(15)N(3)S, the almost planar 2-benzyl-idenehydrazinecarbothio-amide unit (r.m.s. deviation = 0.0351 Å) is aligned at a dihedral angle of 64.42 (6)° with respect to the plane of the tolyl ring. The mol-ecule exhibits an E configuration for the azomethine linkage. In the crystal, inter-molecular N-H⋯S hydrogen bonds about centers of inversion lead to the formation of ...

Benzo[a]quinolizine-2-one derivatives are readily assembled from 1,2,3,4-tetrahydroisoquinoline and β-ketoaldehydes by means of a new intramolecular redox-Mannich process. These reactions are promoted by simple acetic acid and are thought to involve azomethine ylides as reactive intermediates.

The development of more active C-H oxidation catalysts has inspired a rapid, scalable, and stereoselective assembly of multifunctional piperazines through a [3+3] coupling of azomethine ylides. A combination of visible-light irradiation and aluminum organometallics is essential to promote this transformation, which introduces visible-light photochemistry of main-group organometallics and sets t...

In the title benzoyl-hydrazide derivative, C15H14N2O2, the dihedral angle between the planes of the two phenyl rings is 12.56 (9)°. The azomethine double bond adopts an E configuration stabilized by an N-H⋯O hydrogen bond. In the crystal, the components are linked by C-H⋯O inter-actions to form chains along the b axis.

Azomethine ylides are accessed under mild conditions via benzoic acid catalyzed condensations of 1,2,3,4-tetrahydroisoquinolines or tryptolines with aldehydes bearing a pendent dipolarophile. These intermediates undergo intramolecular [3 + 2]-cycloadditions in a highly diastereoselective fashion to form polycyclic amines with four new stereogenic centers. Challenging substrates such as piperidi...

Polysubstituted pyrroles were regioselectively synthesized in moderate to good yields via the copper acetate-catalyzed [3 + 2] annulation reaction of readily accessible aziridines and nitroalkenes. This reaction was proposed to proceed through a key azomethine ylide intermediate generated by selective C-C bond cleavage of the aziridine followed by annulation with nitroalkenes under aerobic cond...

In the title Schiff base compound, C10H12BrN3OS, the C-N-N-C torsion angle is 172.07 (11)°. An intra-molecular hydrogen bond exists between the hy-droxy H atom and the azomethine N atom. In the crystal, pairs of hydrogen bonds involving the imino H atom and the S atom give rise to supra-molecular dimers.

The title compound, C15H14N2O4 adopts an E conformation about the azomethine double bond. Intra-molecular N-H⋯O and O-H⋯N hydrogen bonds generate S(6) rings and help to establish the molecular conformation. The dihedral angle between the benzene rings is 17.84 (10)°. In the crystal, mol-ecules are linked by O-H⋯O and C-H⋯O hydrogen bonds into a two-dimensional network with a herring-bone patter...