, B 8 , and B 9 has not been clarified, but the proposed mechanism would require only a minimal rearrangement of the bonds (one DSD rearrangement and the closing of the cluster after the loss of B 1 ). The loss of B 1 , which is not part of the open face, is surprising. Quantum-mechanical computations might give indications about the feasibility of the proposed pathway, the relative stability of the proposed intermediates, the origin of the H atoms which leave together with B 1 , and the rearrangement of the other H atoms. Experimental Section1, 8±12: Isopropylamine (0.1 g, 1.74 mmol) was added to a solution of (Me 2 S)B 9 H 13 in dry benzene (10 mL, 0.1 g) at room temperature. The mixture was heated to reflux for 3 h. All volatile components were removed under vacuum and the resulting substance was recrystallized from ethanol:water (1:1). Compounds 8 and 9 were purified by TLC by using CH 2 Cl 2 as eluent (R f ¼ 0.31). For further purification the substance was dissolved in CHCl 3 :hexane (1:3) at À20 8C. The solution was filtered and the resulting filtrate was evaporated to dryness to yield the purified product. 1 (DCI): m/z (%) 214 (95)

Based on perfluoro‐tagged benzyl alcohol adsorbed via fluorous–fluorous interactions on fluorous reversed‐phase silica gel (FRPSG), we have performed a multistep synthesis leading finally to a small library of quinazoline‐2,4‐diones. The whole reaction sequence runs without isolation of intermediates and most importantly, without the need of perfluorinated solvents.

This paper describes the behavior of various generations of polyglycerol dendrimers that contain a perfluorinated shell. The aggregation in organic solvents is based on supramolecular fluorous-fluorous interactions, which can be described by means of (19)F NMR spectroscopy. In order to study the interaction and aggregation phenomena of dendrimers with perfluorinated shell and perfluoro-tagged guest molecules we investigated [G3.5]-dendrimer with a perfluorinated shell in the presence of perfluoro-tagged disperse red. Noteworthy, the interaction intensities varied in an unexpected manner depending on the equivalents of perfluoro-tagged guest molecules added to the dendrimers in solution which then formed supramolecular complexes based on fluorous-fluorous interactions. We found that these complexes aggregated around residual air in the solvent to form stable micron-sized bubbles. Their sizes correlated with the interaction intensities measured for certain dendrimer-guest molecule ratios. Degassing of the solutions led to a quasi phase separation between organic and fluorous phase, whereby the dendrimers formed the fluorous phases. Regassing the sample with air afforded bubbles of the initial size again.

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Immobilization of a perfluoro-tagged palladium catalyst on a fluorous reversed-phase silica gel provides a catalyst suitable for Suzuki and Sonogashira cross coupling reactions. The catalytic activities are comparable to those obtained in liquid-liquid fluorous biphasic reactions. The catalyst recovery and reuse is generally possible but depends on the electronic nature of coupling partners used. -(TZSCHUCKE, C. C.; MARKERT, C.; GLATZ, H.; BANNWARTH*, W.; Angew. Chem., Int. Ed. 41 (2002) 23, 4500-4503; Inst. Org. Chem. Biochem., Albert-Ludwigs-Univ., D-79104 Freiburg/Br., Germany; Eng.) -Mischke 14-066

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