A porphyrin-based``molecular square'' (1), prepared by reaction of a dipyridylporphyrin species with Re(CO) 5 Cl and subsequently with Zn II acetate, was functionalized with 2-(methylene-15-crown-5-ether)-nicotinoyl ester (2). Functionalization was achieved by axially ligating each of the four available Zn II sites within the porphyrins. (2) was synthesized by reaction of 2-(hydroxymethyl)-15-crown-5-ether and nicotinoyl chloride in CH 2 Cl 2 . Functionalization renders the square's¯uorescence emission intensity responsive to added Na and, to a lesser extent, K .

Crown ethers bound to microporous polystyrene resins by oxyethylene spacers were prepared by the reaction of monoazacrown ethers with 2‐tosyloxyethoxymethylated or 2‐(2‐tosyloxyethoxy)ethoxymethylated polystyrene resins crosslinked with 2 mol % of divinylbenzene. The activity of the immobilized lariat crowns for halogen exchange reactions under triphase conditions has been studied as a function of catalyst structure, loading, substrate structure, reagent structure, and solvent. The lariat catalysts with extra oxygen donors in the spacer chain exhibited higher activity than the corresponding immobilized catalysts without the donors in the spacer. The increased activity of the catalyst containing 15‐crown‐5 unit and two extra donors for the reaction of 1‐bromooctane with KI was concluded to result from the enhanced complexation with the K+ ion, induced by the cooperative coordination of the crown unit donors and the donors in the spacer chain. The recovered catalysts could be re‐used without decrease in activity.

Soluble or insoluble polystyrenes with hydroxyl-containing polyetheramine structures were prepared by the reaction of linear or crosslinked polystyrenes containing haloalkyl, tosyloxyalkyl, or epoxy groups with bis(2-(2-hydroxyethoxy)ethyl)amine (ATEG). The soluble polystyrenes with ATEG residue afforded polymeric alkoxides by the reaction with aqueous NaOH or KOH under two-phase conditions. The introduction of oxygen-containing spacer chains between ATEG residue and the polymer backbone resulted in the formation of cryptand-like alkoxides, in which the counter cations were bound by cooperative coordination of the oxygen donors in the ATEG residue and in the spacers. The soluble and insoluble polymers with ATEG residue exhibited high catalytic activity for the dehydrobromination of 2-bromoethylbenzene with aqueous NaOH or KOH under two-and three-phase conditions, respectively. The extra coordination of the oxygen donors in the spacers resulted in increased catalytic activity.

This study was to measure the exposure of diesel vehicle drivers to elemental carbon (EC) as an indicator of diesel particulate matter (DPM) emitted from diesel vehicles in an underground coal mine over 3 years as per NIOSH Method 5040. Our study results (range 10 μg/m 3-377 μg/m 3 for the loader drivers, 19 μg/m 3-162 μg/m 3 for the SMV drivers) were similar or less than previous study results (range 5 μg/m 3-2,200 μg/m 3) for normal mine operations. From this study results, it appeared that the exposures decreased in the second and the third year. It is thought that the reasons for the decreased personal DPM (EC) exposures over the 3 years were related to the following recommendations; more frequent monitoring and maintenance of the diesel vehicles and their DPM filtration systems, more consistent monitoring of the mine's ventilation system and changes of work practices such as minimizing the opening of diesel vehicle windows. An educational program on adverse health effects of exposure to DPM and use of respiratory protection (P2 respirators) also assisted in minimizing driver exposure to DPM.

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