New macrocyclic malonates 2–5 have been prepared by reaction of malonyl dichloride with alkanediols. Reactions of these cyclo‐[n]‐alkylmalonates with C60 are highly regioselective. The macrocycles containing identical alkyl spacers selectively form bis‐ and trisadducts of C60 with rotational symmetry. The addition pattern of the regioselectively formed oligoadducts is determined by the size of the alkyl spacer within the macrocyclic malonate. A variety of bis‐, tris‐, tetra‐, and hexaadducts have been synthesized to show the scope of this approach. “Exotic” addition patterns such as trans‐4,trans‐4,trans‐4, which has been synthesized and completely characterized for the first time, are also accessible by this method. The regioselectivity is ruled by the even distribution of the strain within the macrocyclic malonates containing spacer alkane chains of identical lengths: addition patterns with rotational symmetry provide exactly identical distances of the malonate oxygen atoms and are thus exclusively formed by this method. In contrast, when macrocycles with two different alkyl spacer lengths are used, such as 9 and 10, the reaction exclusively yields Cs‐symmetric bisadducts.

Attempted synthesis of the donor-acceptor complex (BDI)Ca ←Al (BDI) complex by reaction of (BDI)Ca in the form of its B(C F ) salt with (BDI)Al in benzene led to dearomatization of the solvent and formation of (BDI)Ca (C H )Al (BDI) (BDI=CH[C(CH )N-Dipp] , Dipp=2,6-diisopropylphenyl). The C H anion is strongly puckered and its boat form features four long (ca. 1.50 Å) and two short (ca. 1.34 Å) C-C bond distances. The flagpole positions of the C H anion chelate an Al cation giving a norbornadiene-like fragment with Al in the 7-position. The C=C double bonds of this alumina-norbornadiene strongly coordinate to the Ca metal ion. The complex is stable in solution up to 80 °C. Several mechanisms for its formation are discussed including a highly likely frustrated Lewis pair type mechanism in which benzene is activated by the Lewis acid (BDI)Ca followed by nucleophilic attack by the Lewis base (BDI)Al .

We report here on the selective synthesis of fullerene pentakisadducts 3 with an incomplete octahedral addition pattern by means of mixed [5:1]hexakisadducts 1 that involve an isoxazoline moiety as a protection group. The isoxazoline addend can be cleanly cleaved by irradiation with light. By using this protection-deprotection strategy, a variety of fullerene pentakisadducts 3 were synthesized in 29-44% overall yield without the need of HPLC purification. This novel photolytic deprotection of 1 can be explained by an initial electron transfer that leads to a biradical, which can easily eliminate the isoxazoline added. The very efficient and straightforward syntheses of the bisfullerene 4 and the globular hexakisadduct 7, each of which involves mixed octahedral addition patterns, clearly demonstrate the advantage of fullerene pentakisadducts 3 as suitable precursors for the construction of highly functional and complex [5:1]hexakisadduct architectures. Complete structural characterization of all new compounds was carried out by MALDI mass spectrometry, UV/Vis, FTIR, (1)H NMR and (13)C NMR spectroscopy, as well as X-ray diffraction.

Heteroleptic alkaline earth metal (Ae = Ca, Sr, Ba) amide complexes with the superbulky β-diketiminate ligand DIPePBDI (CH­[C­(Me)­N-DIPeP]2, DIPeP = 2,6-di-iso-pentylphenyl) have been prepared by direct deprotonation of DIPePBDI-H with either AeN′′2 or AeN′′2·(THF)2 (N′′ = N­(SiMe3)2). Despite long reaction times of 5–14 days, this convenient one-step synthetic method has the major advantage that metal-pure products are obtained in generally quantitative yields. All (DIPePBDI)­AeN′′ and (DIPePBDI)­AeN′′·THF complexes are monomeric and stabilized by agostic metal···Me3Si and metal···iso-pentyl interactions. They are highly soluble in toluene and indefinitely stable toward ligand scrambling, even after 2 weeks at 140 °C. The same series with the smaller DIPPBDI ligand (CH­[C­(Me)­N-DIPP]2, DIPP = 2,6-di-iso-propylphenyl) could, except for Ca, also be prepared by direct ligand deprotonation. The (DIPPBDI)­CaN′′ and (DIPPBDI)­CaN′′·THF complexes are stable toward ligand exchange up to 110 °C. Whereas THF-free (DIPPBDI)­SrN′′ and (DIPPBDI)­BaN′′ decompose at 50 and 20 °C, respectively, their THF adducts were found to be stable up to 60 °C. This is, however, strongly dependent on complex purity. Slight hydrolysis or contamination with KN′′ accelerates ligand scrambling. Therefore, partial hydrolysis and salt metathesis routes that involve KN′′ should be avoided when synthesizing heteroleptic complexes of the heavier Ae metals.

A feasible two-step synthesis and characterization of a full series of hexaarylbenzene (HAB) substituted porphyrins and tetrabenzoporphyrins is presented. Key steps represent the microwave-assisted porphyrin condensation and the statistical Diels-Alder reaction to the desired HAB-porphyrins. Regarding their applications, they proved to be easily accessible and effective high molecular mass calibrants for (MA)LDI mass spectrometry. The free-base and zinc(II) porphyrin systems, as well as the respective tetrabenzoporphyrins, demonstrate in solid state experiments strong red- and near-infrared-light emission and are potentially interesting for the application in "truly organic" light-emitting devices. Lastly, they represent facile precursors to large polycyclic aromatic hydrocarbon (PAH) substituted porphyrins. We prepared the first tetra-hexa-peri-hexabenzocoronene substituted porphyrin, which represents the largest prepared PAH-porphyrin conjugate to date.