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.

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A variety of achiral and chiral macrocyclic oligomalonates were synthesised in a one-step procedure through condensation of malonyl dichloride with α,ω-diols. We have investigated the applicability of this method by varying the length and type of the spacers in the diol. Product distribution analysis revealed that the preferential formation of monomeric, dimeric, or trimeric macrocyclic malonates can be controlled by choosing diols with specific spacers connecting the hydroxy groups. Of special interest are the macrocyclic bismalonates, as they show pronounced crystallisability and arrange into columnar motifs in the solid state. They feature distinctive

This paper addresses the synthesis and characterization of a novel temperature‐ and pH‐responsive nanogel system based on poly(vinylcaprolactam‐co‐2‐dimethylaminoethyl methacrylate) [P(VCL‐co‐DMAEMA)] by using a surfactant‐free emulsion polymerization procedure for the multiresponsive drug delivery of hydrophobic drugs. The effects of solvent, monomer, pH, and temperature were studied to tailor the average particle hydrodynamic diameters and the polydispersity index of the final particles. According to dynamic light‐scattering measurements, the obtained nanogels show a narrow particle‐size distribution and their hydrodynamic diameters can be varied from 81 to 368 nm. The nanogels display a re‐entrant phase‐transition state, and the equilibrium volume swelling ratio of the nanogels decreases drastically down to 47 °C and then increases up to 65 °C. In addition, the nanogels show pH‐dependent behavior. They exhibit a maximum size at pH 5.0. Rhodamine B (RhB) was chosen as a model compound for drug loading and release studies from P(VCL‐co‐DMAEMA) on the basis of particles in different phosphate buffer solutions at different temperatures. The temperature/pH‐dependent cumulative release and ultrasound‐enhanced pulsatile release properties were investigated for RhB‐loaded nanogels for long‐term and one‐shot delivery. The nanogels display efficient delivery for both long‐term and one‐shot delivery systems. We provide here a proof of concept for the novel use of multiresponsive nanogels having an overall size below 200 nm as a cargo system for hydrophobic drugs and for controlled release mediated by temperature/pH and ultrasound.