Anhydrooligomers of o-aminobenzaldehydes—the rich chemistry of the Busch macrocycles1Dedicated to Professor Daryle H. Busch on the occasion of his 70th birthday.1

Campestarenes: novel shape-persistent Schiff basemacrocycles with 5-fold symmetry

“…12 Synthesis of macrocycles from a single precursor containing both the amino and formyl groups has been studied in a few cases, but the macrocycles are usually obtained in low yields, as a mixture of different sizes, or templated by a metal ion that cannot be removed afterward. [13][14][15] Here we present a new family of macrocycles (1a-c) with 5-fold symmetry that have hydroxyl groups to stabilize the imine with a hydrogen bond and direct the macrocycle size. As these new macrocycles are flat and tend to aggregate in solution and in the gas phase, they are promising for new studies in supramolecular chemistry.…”

(Alkyliminomethyl)phenylamido and related complexes of zirconium and titanium

“…The self-condensation of o-aminobenzaldehyde gives cyclic trimeric and tetrameric products, which were unambiguously characterised. 12 If the condensation is carried out in the presence of metal templates, macrocyclic complexes with the "faceblocking" trimer A or the planar "porphyrin-like" tetramer B (Scheme 3) are obtained; the first compounds of this type were realised and characterised in 1965 by Busch. 12 Furthermore, complexes with A and B can react with strong nucleophiles (R Ϫ , RO Ϫ , RS Ϫ etc.)…”

“…12 If the condensation is carried out in the presence of metal templates, macrocyclic complexes with the "faceblocking" trimer A or the planar "porphyrin-like" tetramer B (Scheme 3) are obtained; the first compounds of this type were realised and characterised in 1965 by Busch. 12 Furthermore, complexes with A and B can react with strong nucleophiles (R Ϫ , RO Ϫ , RS Ϫ etc.) at the azomethine carbons giving derivatives with functionalised anionic macrocycles.…”

The d-L(π)-π type of charge-transfer salt [Cu(Me-tri)2][Ni(dmit)2]2: Interaction between copper(ii) d- and Ni(dmit)2π-electrons via π-conjugated macrocyclic ligands

“…5 The large L(p) of Cu(Me-tri) 2 is advantageous for forming contacts with Ni(dmit) 2 via L(p)-p overlap. In addition, it is expected that the p-orbital levels of macrocyclic L(p) such as Me-tri are close in energy to the dorbital levels of transition metals, leading to d-L(p) orbital mixing; 6 thus, the copper(II) spin (S ¼ 1/2) should be delocalized over the outside sphere of the complex. For these reasons, Me-tri is a promising ligand to link copper d-and Ni(dmit) 2 pelectrons.…”