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A simp le method for the synthesis of 4-{((dimethyl)azanylidenonium ch loride) methyl}amino-2,3-dihydro- 3-o xo -4H-1,2,4,3-t riazaphosphole (2) is described. Treat ment of phosphonic dihydrazide (1 ) with Vilsmeier-Haack reagent led direct ly to the title co mpound in high yield.

Methyl chloride (CH3Cl), methyl bromide (CH3Br), and methyl iodide (CH3I) in marine boundary air were measured over the western Pacific and the southeastern Indian Ocean during the period of December 1996–February 1997. The mean concentrations of CH3Cl, CH3Br, and CH3I were 623, 10.3, and 1.1 pptv, respectively, and their highest concentrations were observed in the tropics. The enhancement of CH3Cl concentration in the tropics, particularly near islands, was consistent with the recently reported finding on its high emissions from tropical coastal lands. The enhancement of CH3Br in the tropics was not related to the closeness of the sampling sites to islands, suggesting that land sources were not so important for CH3Br as for CH3Cl. The atmospheric CH3I concentrations showed a little higher concentration in the tropics and in the southern hemisphere (SH) than in the northern hemisphere (NH). This finding suggests that its higher emission from the tropics and SH in austral summer compensates the higher rate of photolytic decay of this compound in the regions.

Palladium methyl complexes with potentially terdentate pyridylthioether (S-N-S(R) = 2,6-bis(R-thiomethyl)pyridine, R = Me, t-Bu, Ph; N-S-N = 2[(2-pyridylmethylthio)methyl]-pyridine) ligands have been prepared and characterized. Both the bidentate chloride [Pd(Me)(S-N-S(R))]Cl and the terdentate chloride-free [Pd(Me)(S-N-S(R))] + species are present in solution and display a substantially different reactivity toward allene insertion across the Pd-C bond. The structures of the complexes [Pd(Me)(S-N-S(t-Bu))]OTf and [Pd(Me)(S-N-S(t-Bu))Cl were determined by X-ray diffraction. The chloride methyl substrates [Pd(Me)(S-N-S(R))]Cl display an enhanced reactivity in solution with respect to the allene insertion, and this reactivity was traced back to the distortion of the main coordination plane induced by the presence of an uncoordinated -CH 2 -S-R group in position 6 of the coordinating pyridine. The equilibrium position between the terdentate and the bidentate species can be modulated by addition of chloride ion, which therefore controls the overall reactivity of the system.

Procedures are given for direct conversion of hexadecan-1-ol tetrahydropyranyl ether to the corresponding bromide, chloride, methyl ether, nitrile, and trifluoroacetate.

Role d'espaceur inerte des motifs chlorure de vinylidene qui diminuent les associations intramoleculaires entre les dipoles carbonyl des motifs MMA du copolymere. Stabilite thermique minimale des copolymeres lorsque le nombre de motifs MMA et VDC adjacents est maximal; degradation thermique via une cyclisation intramoleculaire et perte de HCl pour donner une lactone a 5 chainons insatures

The development of modern scientific and engineering technology reqires recording materials that are capable of instantaneous recording and displaying. Polymer can be used as photosensitive materials. for this purpose. Two such recording materials i.e the acid sensitive colour changing recording material and PVK film have be studied and developed in our laboratory. It was found they are sensitive to the deep UV light, near UV light, electron bean and other high energy radiation etc. Experiments were also perfomed to study the change of photosensitive characteristics upon radiation. The mechanism of image formation and thier applications are discussed.

The rotational spectra of CH 3 35 Cl, CH 3 37 Cl, CH 3 79 Br, CH 3 81 Br, and CH 3 I in the ν 6 state were observed between 8 and 240 GHz. For CH 3 Br and CH 3 I, the present data were combined with the pure quadrupole resonances of Oka et al. to determine the molecular constants. Our measurements have enabled us to notably improve the molecular constants for the ν 6 excited states.

The vapor phase infrared spectra to 300 cm−1 are discussed and assignments made for the compounds (CH3)6Al2, (CD3)6Al2, (CH3)4Al2Cl2, (CD3)4Al2Cl2, (CH3)2Al2Cl4, CH3TiCl3, CD3TiCl3, and (CH3)2TiCl2. The assignments differ significantly from those previously published, but are consistent throughout the series of aluminum compounds and with related spectra. The data are in agreement with a bridged structure for trimethyl aluminum of D2h or C2h symmetry and with a bridged structure of dimethyl aluminum chloride with chlorine bridging. The dimer (CH3)2Al2Cl4 is shown to exist in the trans configuration. Evidence is presented indicating that an impurity is commonly found in spectra of dimethyl aluminum chloride which is identified as the mixed dimer (CH3)3Al2Cl3, aluminum sesquichloride. A number of anomalies observed in the spectra of the methyl titanium compounds are pointed out and discussed.

The parallel type bands ν5 for CH3Cl, CH3Br and CH3I have been found at λ13.7, 16.4 and 18.8μ, respectively, the rotation lines of the chloride band being partially resolved. The iodide band has a particularly sharp zero branch suitable for use in calibration. Both the chloride and bromide bands are complicated by isotopic effects, the separations being 6 cm—1 and 1 cm—1.