Palladium-catalyzed aminoallylation of activated olefins with allylic halides and phthalimide

The three-component aminoallylation reaction of the activated olefins 2 with the phthalimide 1a and allyl chloride proceeded very smoothly in the presence of Pd(2)dba(3).CHCl(3) (5 mol %)/P(4-FC(6)H(4))(3) (40 mol %) and Cs(2)CO(3) (3 equiv against 2) in dichloromethane at room temperature to give the corresponding aminoallylated products, N-pent-4-enylphthalimides 3, in 58-99% yields. The reaction of oxazolidinone 1b also proceeded very smoothly to give N-(2,2-dicyano-1-phenylpent-4-enyl)oxazolidinone in a quantitative yield; however, the Tsuji-Trost-type allylation products 4 were obtained in the case of dibenzylamine, N-tosylaniline, and pyrrolidin-2-one. Further, 2 underwent cycloaddition with N-tosylvinylaziridine 9a in the presence of Pd(2)dba(3).CHCl(3) (5 mol %)/P(4-FC(6)H(4))(3) (40 mol %) in THF at room temperature, giving the corresponding pyrrolidines 11 in 69-99% yields.     

Dynamic stability of carbonyl ylides

The non- and fluorine-substituted singlet carbonyl ylides are studied by using ab initio MCSCF calculations. The thermodynamic stability of the carbonyl ylides and the intramolecular stability to isomerization or fragmentation reaction coordinates is demonstrated in terms of the topological structure of the ab initio potential energy surfaces. The allylic resonance is found to be dynamically unstable, considering out-of-plane vibrational mode. The instability is studied by the symmetries of the low-lying excitations out of the MCSCF wave function.     

Electrophoretic mobility of a charged cylindrical colloidal particle covered with an ion-penetrable uncharged polymer layer

Expressions are derived for the electrophoretic mobility of a cylindrical charged colloidal particle carrying a low zeta potential covered with an ion-penetrable uncharged polymer layer in an electrolyte solution. These expressions involve numerical integration of modified Bessel functions but are easily calculable with Mathematica. The obtained mobility expressions are a modification of Henry's mobility formula for a cylindrical particle taking into account the presence of the uncharged polymer layer.     

Ultraweak Luminescence Generated by Sweet Potato and Fusarium oxysporum Interactions Associated with a Defense Response

Abstract— Ultraweak luminescence generated by sweet potato and nonpathogenic Fusarium oxysporum interactions associated with a defense response was detected by a photoncounting method using ultrahigh-sensitive photodetectors. The time-dependent intensity variation, the spectrum and the two-dimensional imaging of the ultraweak luminescence are indicative of the defense response of the sweet potato to F. oxysporum. The production of ipomeamarone as a phytoalexin means that F. oxysporum induced the defense response in the sweet potato.     

Determination of a polymeric hindered amine light stabilizer in polypropylene formulated with magnesium hydroxide flame retardant by reactive thermal desorption-gas chromatography.

A polymeric hindered amine light stabilizer (HALS), Tinuvin 622 (MW [symbol: see text] 4000), in PP materials formulated with a magnesium hydroxide flame retardant was determined by reactive thermal desorption (RTD) gas chromatography (GC). Two kinds of the HALS components that were formed through the RTD in the presence of tetramethylammonium hydroxide [(CH3)4NOH, TMAH] were clearly observed in the chromatograms of the PP samples, with negligible interference from the other additives and the PP substrate. Here, the coexisting flame retardant was proved to affect significantly the RTD process of the occluded HALS. As a result, the recovery of the HALS components in the RTD-GC chromatograms of the PP samples increased with increase in the content of the flame retardant. This enhancement of the HALS recovery is attributed mainly to the preferential exposure of the HALS on the surface of the ground PP sample through the interaction between the polymeric HALS and the flame retardant in the molten PP during kneading. In spite of such a considerable action of the flame retardant, the observed intensities of the characteristic peaks of HALS by RTD-GC showed a good linear relationship with the HALS content in the PP samples with constant content of the flame retardant (50 phr); this relationship could be used as the calibration line for the determination of the polymeric HALS in the PP materials containing the flame retardant.     

Synchronized sailing of two camphor boats in polygonal chambers

The synchronized self-motion of two camphor boats on polygonal water chambers was investigated. The two boats synchronously moved depending on the number of corners in the polygon by changing the distance between the two boats through the corners. We regard the self-motion of a camphor boat as an oscillator; i.e., one cycle on the polygonal chamber corresponds to 2pi. Phase-locked synchronization at a phase difference of 2pi/3, which corresponds to the length of one side of the chamber, was observed with a triangular chamber. Two types of synchronized motion at phase differences of pi/2 and pi, which correspond to the length of one and two sides of the chamber, respectively, were observed with a square chamber. These characteristic features of synchronized self-motion were qualitatively reproduced by a numerical calculation that regarded the surface tension as the driving force and the number of corners in the chamber as a velocity-regulating mechanism. We believe that the present system may be a simple model of synchronization which depends on the geometry of the system.     

Meso-tetrakis[o-(N-methyl)pyridinium]porphyrin ensembles with axially coordinated cyclodextrin-penetrating phenethylimidazole: reversible dioxygen-binding in aqueous DMF solution

alpha-Cyclodextrin (alpha CD)-penetrating 2-methyl-1-phenethylimidazole coordinates to the zinc(II) and iron(II) complexes of meso-tetrakis[o-(N-methyl)pyridinium] porphyrinate, giving non-covalently linked alpha CD-porphyrin ensembles; the iron(II) complex can reversibly bind and release dioxygen in aqueous DMF solution.