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Gaining external control over self-organization is of vital importance for future smart materials. Surfactants are extremely valuable for the synthesis of diverse nanomaterials. Their self-assembly is dictated by microphase separation, the hydrophobic effect, and head-group repulsion. It is desirable to supplement surfactants with an added mode of long-range and directional interaction. Magnetic forces are ideal, as they are not shielded in water. We report on surfactants with heads containing tightly bound transition-metal centers. The magnetic moment of the head was varied systematically while keeping shape and charge constant. Changes in the magnetic moment of the head led to notable differences in surface tension, aggregate size, and contact angle, which could also be altered by an external magnetic field. The most astonishing result was that the use of magnetic surfactants as structure-directing agents enabled the formation of porous solids with 12-fold rotational symmetry. published

Herein, we report on the reaggregation of hexameric trimethylsilylmethyllithium [LiCH2SiMe3]6 with the donor base DABCO (1,4-diazabicyclo[2.2.2]octane) to give the unprecedented octamer [(DABCO)7·(LiCH2SiMe3)8] (1). The structure consists of four dimers, forming Li2C2 four-membered rings, connected to two [(DABCO)3·{(LiCH2SiMe3)2}2] chain fractions, interconnected by a single DABCO molecule. Interestingly, two different conformers of (LiCH2SiMe3)2 dimers are present, caused by different steric demand. Higher steric strain in the center of the molecule causes an ecliptic arrangement of the Me3Si group along the Si–Cα bond, while at the periphery the more relaxed staggered conformation is enabled. The reactivity of trimethylsilylmethyllithium coordinated by DABCO was tested in the benchmark reaction with toluene. Although the aggregation of 1 is much higher than that of the parent [LiCH2SiMe3]6, the reactivity of the first is higher than that of the starting material, provided the octameric aggregation foun...