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The objectives of this program are to: (1) prepare polyketones and polysulfones by the partial substitution of CO or SO/sub 2/ for ethylene; and (2) determine their market value as low-cost energy-conserving polymers. Additional quantities of Et-CO copolymers were prepared at 680 atm, as well as at 340 atm, by Co-60 gamma radiation induced polymerization for product evaluation by Tenneco Chemicals, Inc. (TCI). The preparative phase of the joint program with TCI is thus concluded. The final results and summary of the product evaluation study by TCI will be forthcoming shortly. Work was continued on polymerization rates for gas-phase Et-SO/sub 2/ mixtures at low pressure (< 10 atm) by Co-60 gamma radiation induced polymerization. Maximum rates were obtained in recharged vessels at SO/sub 2/ concentrations of < 5 mole % and at approximately 50 mole %. The peak rates appear to be directly proportional to the pressure. The peak G-values appear to be independent of pressure and are about the same for the two gas compositions, averaging approximately 8 x 10/sup 4/ molecules/100 eV.

The oxidation of the S/sub 3/N/sub 3//sup -/ ion in acetonitrile solution by molecular oxygen gives rise to four major products: S/sub 4/N/sub 5//sup -/, S/sub 4/N/sub 5/O/sup -/, S/sub 3/N/sub 3/O/sup -/, and S/sub 3/N/sub 3/O/sub 2//sup -/. The relative yields of these species are a function of the flow rate of oxygen, and the progress of the reaction and the structure of the various ions in solution can be analyzed by using /sup 15/N NMR spectroscopy. The crystal and molecular structures of (Ph/sub 3/P)/sub 2/N/sup +/S/sub 3/N/sub 3/O/sup -/ and (Ph/sub 3/P)/sub 2/N/sup +/S/sub 3/N/sub 2/O/sub 2//sup -/ have been determined by x-ray diffraction. Crystals of the former are monoclinic, space group P2/sub 1//c, with a = 17.161 (2) A, b = 9.970 (1) A, c = 20.591 (2) A, ..beta.. = 104.45 (1)/sup 0/, V = 3411.7 A/sup 3/, and Z = 4. Crystals of the latter are monoclinic, space group P2/sub 1/, with a = 12.421 (1) A, b = 13.036 (1) A, c = 10.699 (1) A, ..beta.. = 103.36 (1)/sup 0/, V = 1685.6 A/sup 3/, and Z = 2. Both structures were solved by direct methods and refined by full-matrix least-squares procedures; formore » (Ph/sub 3/P)/sub 2/N/sup +/S/sub 3/N/sub 3/O/sup -/ the final R = 0.053 and R/sub w/ = 0.075 for 3058 reflections with I > 3sigma(I), and for (Ph/sub 3/P)/sub 2/N/sup +/S/sub 3/N/sub 3/O/sub 2//sup -/ the final R = 0.048 and R/sub w/ = 0.057 for 2312 reflections with I > 3sigma(I). The two anions S/sub 3/N/sub 3/O/sup -/ and S/sub 3/N/sub 3/O/sub 2//sup -/ both possess six-membered S/sub 3/N/sub 3/ ring structures with exocyclic oxygen atoms bonded to sulfur (in S/sub 3/N/sub 3/O/sub 2//sup -/ the oxygens are geminally substituted). Both rings exhibit significant variations in chemically equivalent bond lengths and angles. The visible spectra of S/sub 3/N/sub 3/O/sup -/ (lambda/sub max/ = 509 and 340 nm) and S/sub 3/N/sub 3/O/sub 2//sup -/ (lambda/sub max/ = 562 and 362 nm) are interpreted in terms of the expected perturbations on the ..pi..-manifold of the S/sub 3/N/sub 3//sup -/ anion; the observed absorptions are assigned to ..pi..* ..-->.. ..pi..* type excitations. 34 references, 5 figures, 6 tables.« less

An expedient synthesis of previously unknown (1 Z , 3 Z )-1, 4-dibromobutadiene is reported. When this dibromide is treated with s- or t-butyllithium, (1 Z , 3 Z )-1-bromo-4-lithio-butadiene is generated. Treatment of the dibromide with four equivalents of t-butyllithium gives (1 Z , 3 Z )-dilithiobutadiene. Reaction of (1 Z , 3 Z )-1-bromo-4-lithiobutadiene with (η 5 -C 5 H 5 )Fe(CO) 2 I gives (1 Z , 3 Z )-(η 5 -C 5 H 5 )Fe-(CO) 2 CH=CHCH=CHBr. X-ray crystallographic analysis of this latter compound establishes the geometry about the bromobutadiene ligand.

Preparation de complexes du ruthenium (II) de type ru(bpy) 2 (HSO 3 )L ou L=H 2 O, SO 3 2− , pyridine et bpy-bipyridine. Etude en solution par voltammetrie cyclique et equilibres acidobasiques. Etude radiocristallographique

BenzylCo(dmgH)(dpgH)Py has been synthesized by the reaction of benzyl chloride with a mixture of Co I (dmgH)2Py and Co I (dpgH)2Py, generated in situ, by the NaBH4 reduction of ClCo(dmgH)2Py and ClCo(dpgH)2Py. A mixture of three products is formed. The first crystal structure of an organocobaloxime with a mixed-dioxime ligand is reported. © 2000 Elsevier Science S.A. All rights reserved.

C 14 H 11 N 3 OS cristallise dans le systeme orthorhombique avec le groupe d'espace Pbca. Affinement de la structure jusqu'a 0,044. La portion N 3 C 2 du cycle est plane

C 16 H 36 As 4 S 4 cristallise dans P2 1 /c avec affinement jusqu'a 0,038. L'heterocycle a une conformation «crown» (S 8 ) ou les groupes exo occupent les positions equatoriales