In this paper, we describe a new polymerization manner termed as “vine‐twining polymerization” to produce amylose–polymer inclusion complexes. The polymerization was achieved by an enzymatic polymerization of α‐D‐glucose‐1‐phosphate monomer catalyzed by phosphorylase in the presence of polyTHF as a guest polymer. The structure of the product was determined by X‐ray powder diffraction and 1H NMR measurements to be the inclusion complex. The formation process of the inclusion complexes during the polymerization was also evaluated. Furthermore, the formation of the inclusion complexes by this polymerization method by using polyTHFs with various Mns and end groups, as well as other polyethers as the guest polymers, was examined.

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a b s t r a c tThis study aimed to directly and systematically compare the flame inhibition abilities of various transition metals, including vanadium, ruthenium, osmium, chromium, manganese, iron, cobalt, and nickel, by using the corresponding metallocenes: vanadocene, ruthenocene, osmocene, chromocene, manganocene, ferrocene, cobaltocene, and nickelocene. The downward flame spread rates over filter paper samples on which each metallocene was adsorbed were measured. In addition, thermogravimetric measurements were carried out to finally determine the phase in which each metallocene produced its flame inhibition effect. The results indicated that all these metallocenes, with the exception of vanadocene, exhibit a flame inhibition effect solely in the gas phase, whereas vanadocene shows fire suppression ability in the solid phase. This work also found that, in terms of their fire suppression abilities, the transition metals can be ranked in the following order: Cr4Mn4 Fe4 Co4 Ni 4(V 4)Os4 Ru.

COMMUNICATIONSner) for synthesizing interesting new compounds. This extends the chemistry of ferrocene by a basic new variant, and also opens a unique opportunity for the enantioselective-catalytic synthesis of planar-chiral ferrocene derivatives. Experimental SectionGeneral procedure for preparing the cyclization precursors 1-3 from the corresponding ferrocenyl alkanoic acids: To a stirred suspension of the ferrocenyl alkanoic acid (4.1 mmol) in anhydrous benzene (60 mL) was added sodium hydride (4.18 mmol) under an argon atmosphere, and after 10 min pyridine (2.61 mmol). The mixture was cooled to 0 "C, and freshly distilled oxalyl chloride (26.5 mmol) added dropwise. After complete addition stirring was continued for 30 min at 0 "C. for 30 rnin at room temperature, and finally for 1 h at 55°C. After filtration of the reaction mixture through a short pad of silica gel, the solvent and excess oxalyl chloride were completely removed in vacuo The dark brown residue was dissolved in Et,O (15 mL), and a solution ofdiazomethane (35 ml. " 0 . 6~ in Et,O) added at 0 'C. After the reaction mixture was stirred for 20 min at 0 "C excess diazomethane and solvent were completely removed in vacuo, and the residue was purified by flash chromatography (hexaneiEtOAc). General procedure for the cyclization experiments summarized in Table 1 : To a solution of the catalyst (34 pmol; 5 mol%) in the anhydrous solvent (10 mL) was added dropwise at RT under an atmosphere of argon a solution of the diazoketone (0.68 mmol) in the solvent (5 mL) within about 30 min. Gas evolution (NJ indicated the decomposition of the diazo compound. After complete addition stirring was continued until complete conversion was reached (usually about one hour). After rapid filtration of the dark brown reaction mixture through a short pad of silica gel under argon, the solvent was completely removed in vacuo. The products were separated and purified by flash chromatography or radial chromatography (using a chromatotron) under an argon atmosphere. Enantioselective cyclizations: Ligand 17 (17.3 pmol) was added to a solution of Cu'OTf (17 pmol; weighed in a glove box) in CH,CI, (3 mL) under an argon atmosphere. After the reaction mixture was stirred for 2 h at RT, the green solution of the catalyst was heated to reflux, and a solution of the substrate (2 or 3; 0.34 mmol) in CH,CI, (10 mL) slowly added within 2 h with a syringe pump (all under argon). After complete addition the brownish solution was heated at reflux for 20 rnin before being subjected to work-up as described above. The enantiomeric excess of the product was determined with HPLC (Daicel, Chiralcel OJ). 191 All new compounds were characterized by the usual spectroscopic methods (see Table 2) and gave correct elemental analysis and/or high-resolution mass spectra. Self-replication, like the chirality of the components, is one of the most characteristic features of living organisms. Therefore, self-replication of a chiral molecule is of much interest. The concept of self-replication, however, has no...

Das Produkt als Auslöser der Enantioselektivität ‐ dieser Ansatz kennzeichnet die hier vorgestellte Reduktion von α‐Aminoketonen mit Lithiumaluminiumhydrid [G1. (1)]. Indem das Reduktionsmittel vor seinem Einsatz mit dem Produktalkohol als chiralem Liganden modifiziert wird, lassen sich bei Ausbeuten zwischen 65 und 93% ee‐Werte zwischen 69 und 90% erreichen.