Ethylene sulfide, structure

This method has been applied for the synthesis of ethylene sulfide,4 u- 2-47 propylene sulfide, a eia- and gran 2-butene sulfides,74 7 isobutylene sulfide,1 7 cyclohexene Hulfide,1 107 3-lMsethoxypropytoir. sulfide,122 and styrene sulfide.40 A modification of thie reaction ha, been used for the synthesis of carbohydrates possessing episulfidc structures.4 ... 

A determination of bond distance and angles from microwave spectra has been applied to structural studies of ethylene sulfide.21... 

Trimethylene oxide (Hawkins and Davidson, 1966), cyclopropane (Hafemann and Miller, 1969 Majid et al., 1969), and ethylene sulfide (Ripmeester, Personal Communication, May 2,1988) are three molecules that can form in either the 51262 of structure I or the 51264 of structure II as simple hydrates. Raman spectroscopy measurements suggest that a low fraction of 512 cages may also be occupied by cyclopropane at high pressures (Suzuki et al., 2001). Such compounds change structures depending on the temperature and pressure of formation, and guest composition in the aqueous phase as discussed in Section 2.1.3. 

In the polymerization of cyclic sulfides, cyclization becomes particularly important because of the enhanced basicity (and nucleophilicity) of the linear sulfides in comparison with their parent monomers43). The simplest cyclic oligomer, formed in the polymerization of thiiranes, is a dimer-1,4-dithiane or its derivatives. 1,4-Dithiane was first observed by Bell in the polymerization of ethylene sulfide 441 later Price isolated the styrene sulfide dimer 45) and recently Goethals obtained dimers of isobutylene and cyclohexene sulfides 46 . Structures of these dimers are ... 

Carbon-13 spectroscopy has been used very effectively by Corno and coworkers [115-117] to characterize the distributions of monomer sequences in copolymers derived from episulfides using anionic catalysts. Although chiral monomers were not employed in these studies, it is worth noting that tacticity effects had a relatively small effect on the resonance patterns observed, but that the chemical shifts of in-chain carbon atoms in different sequences were s ibstantially different. On the basis of assignments and empirical shift parameters developed by Corno, et al., the spectra of stereoregular ethylene sulfide-propylene sulfide copolymers and propylene sulfide-isobutylene sulfide copolymers should be readily analyzed. Studies on copolymers derived from racemic monomers indicate them to have random structures a similar result can be e3q>ected for copolymers derived from optically active monomers. 

Figure 16 Possible structures for the reaction products of ethylene sulfide with WP-1. A, An aminothiol. B, A polysulfide appended to the polyamine.

It is well known that mercury can form polymeric structures with sulfur-containing ligands where the ratio of the ligand to merciny is less than the 2 1 found in the isolated complex, Hg(S2CNR2)2. Finally, it should be pointed out that the captured mercury on WP-3 resists leaching even with lOM hydrochloric acid, as with WP-1, which is modified with ethylene sulfide. 

It should also be noted that the viscometric technique can detect the presence of star-shaped aggregates, having the ionic active centers. The addition of ethylene oxide to hydrocarbon solutions of poly(isoprenyl)lithium leads to a nearly two-fold increase in viscosity144). Conversely, this results in an approximately twenty-fold decrease in solution viscosity, after termination by the addition of trimethylchloro-silane. This change in solution viscosity is reflected in the gelation which occurs when difunctional chains are converted to the ionic alkoxy active centers 140,145,146). Branched structures have also been detected 147> by viscometry for the thiolate-lithium active center of polypropylene sulfide) in tetrahydrofuran. 

However, the (M)-phenyl methyl sulfoxide has the opposite configuration to (Mi-styrene oxide (Fig. 8, inset) (49). A possible structural difference between styrene and thioanisole is the fact that the ethylene group in styrene is in the plane of the phenyl ring while the S-methyl group in thioanisole is perpendicular to the phenyl group. If the Mb mutants discriminate this steric difference, one could expect (S)-sulfoxide formation if cyclic sulfides are employed as substrates, since the cyclic sulfides should have planar structures (Fig. 8c) similar to styrene. Table III lists representative results of cyclic and acyclic sulfide... 

We begin with the structure of a noble metal catalyst, where the emphasis is placed on the preparation of rhodium on aluminum oxide and the nature of the metal support interaction. Next, we focus on a promoted surface in a review of potassium on noble metals. This section illustrates how single crystal techniques have been applied to investigate to what extent promoters perturb the surface of a catalyst. The third study deals with the sulfidic cobalt-molybdenum catalysts used in hydrotreating reactions. Here, we are concerned with the composition and structure of the catalytically active surface, and how it evolves as a result of the preparation. In the final study we discuss the structure of chromium oxide catalysts in the polymerization of ethylene, along with the polymer product that builds up on the surface of the catalyst. 

Thermal decomposition of methyl xanthates is similar to the pyrolysis of acetates for the formation of the double bond. Olefins are obtained from primary, secondary, and tertiary alcohols without extensive isomerization or structural rearrangement. The other products of the pyrolysis of the methyl xanthates are methyl mercaptan and carbon oxy-sulfide. The xanthates prepared from primary alcohols are more difficult to decompose than those prepared from secondary and tertiary alcohols. Over-all yields of 22-51% have been obtained for a number of tertiary alkyl derivatives of ethylene. Originally the xanthates were made by successive treatment of the alcohol with sodium or potassium, carbon disulfide, and methyl iodide. In a modification of this procedure sodium... 

Self-assembly-based networks Ordered superlattices composed of nanosized semiconducting sulfides have been synthesized within lyotropic phases. Hexagonal-packed arrays of nanocrystalline CdS (or similar structures such as ZnS, Cdi cZn tS, and CdSe) have been produced, a mineral copy of an (ethylene oxide)lo-oleyl/water mesophase presenting periodicities ranging between 7 and 10 nm. 

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