Oxidative vinylation

Because Pd(II) salts, like Hgtll) salts, can effect electrophilic metallation of the indole ring at C3, it is also possible to carry out vinylation on indoles without 3-substituents. These reactions usually require the use of an equiv. of the Pd(ll) salt and also a Cu(If) or Ag(I) salt to effect reoxidation of the Pd. As in the standard Heck conditions, an EW substitution on the indole nitrogen is usually necessary. Entry 8 of Table 11.3 is an interesting example. The oxidative vinylation was achieved in 87% yield by using one equiv. of PdfOAcfj and one equiv. of chloranil as a co-oxidant. This example is also noteworthy in that the 4-broino substituent was unreactive under these conditions. Part B of Table 11.3 lists some other representative procedures. 

ETHYLENE We discussed ethylene production in an earlier boxed essay (Section 5 1) where it was pointed out that the output of the U S petrochemi cal industry exceeds 5 x 10 ° Ib/year Approximately 90% of this material is used for the preparation of four compounds (polyethylene ethylene oxide vinyl chloride and styrene) with polymerization to poly ethylene accounting for half the total Both vinyl chloride and styrene are polymerized to give poly(vinyl chloride) and polystyrene respectively (see Table 6 5) Ethylene oxide is a starting material for the preparation of ethylene glycol for use as an an tifreeze in automobile radiators and in the produc tion of polyester fibers (see the boxed essay Condensation Polymers Polyamides and Polyesters in Chapter 20)... 

The term liquefied petroleum gas (LPG) is often used to describe those liquefied flammable gases that are derived from petroleum. The term LFG is preferred when the discussion applies to all liquefied flammable gases. It includes materials such as ethylene oxide, vinyl chloride, and methylamines, which behave similarly so far as their flashing and flammable properties are concerned. 

ETHYLENE GLYCOL ETHYL MERCAPTAN DIMETHYL SULPHIDE ETHYL AMINE DIMETHYL AMIDE MONOETHANOLAMINE ETHYLENEDIAMINE ACRYLONITRILE PROPADIENE METHYL ACETYLENE ACROLEIN ACRYLIC ACID VINYL FORMATE ALLYL CHLORIDE 1 2 3-TRICHLOROPROPANE PROPIONITRILE CYCLOPROPANE PROPYLENE 1 2-DICHLOROPROPANE ACETONE ALLYL ALCOHOL PROPIONALDEHYDE PROPYLENE OXIDE VINYL METHYL ETHER PROPIONIC ACID ETHYL FORMATE METHYL ACETATE PROPYL CHLORIDE ISOPROPYL CHLORIDE PROPANE... 

Recently, a new class of excipients based on ethylene oxide-vinyl alcohol copolymers (see Figure 17.12) has been developed (PEO-g-PVA). The combination of PVA and PEO should result in an excellent instant-release tablet coating. One way to... 

Several carbonyl-containing peroxide additives have been shown to increase the initial rate of the nonoxidative photo-dehydrochlorination of PVC (54). In studies with polymeric ketones unrelated structurally to PVC, the excited singlet and triplet states of the carbonyl groups in these polymers were found to sensitize 0-0 homolysis at rates approaching diffusion control (55). Similar reactions may well occur in oxidized vinyl chloride polymers. 

VA Machtin. Reactions of Peroxyl Radicals in Oxidizing Vinyl Monomers and Reactivity of Double Bonds. Ph.D. thesis Dissertation, Institute of Chemical Physics, Chernogolovka, 1984, pp 1-18 [in Russian],... 

The use of aqueous foams to control fume or vapour release from reactive chemicals is discussed. An acid-resistant foam NF2 controlled fume emission from 35% and 65% oleum, and from titanium tetrachloride, but was not effective for sulfur trioxide and chlorosulfuric acid. An alcohol-resistant foam NF1 suppressed ammonia vapour emission by 80%, and Universal fire foam reduced evaporation of ethylene oxide, vinyl chloride and methanethiol, and reduced vapour emission of 1,3-butadiene by 60%. Safety aspects of foam blanketing are discussed [1]. Equipment and application techniques are covered in some detail [2],... 

Aflotoxin Bi capsaicin ethylene oxide vinyl chloride... 

Alkenylmagneaium bromides have been reported to condense with ethylene oxide. Vinyl- and taobutenylmagneeium bromide, for example, give the expected y.Sunsaturated alcohols in good yield (Eq. 822). but fj-styrylmagnesium bromide reacts poorly. 164... 

The ion at +121 amu, interpreted as originating from oxidized vinyl groups, is now absent. This suggests that the highly oriented molecules are more resistant to oxidation at room temperature than the randomly oriented molecules in the thick film. 

From the examples above we can conclude that palladium-catalyzed oxidative vinylation of arenes has developed well beyond its inception by Fujiwara in the sixties. Quite good turnovers with 02 as oxidant have now been achieved by use of addi-... 

Palladium-catalyzed Oxidative Vinylation 203 Piet W. N. M. van Leeuwen and Johannes G. de Vries... 

Oxidizes vinylic boranes to yield aldehydes.(Section 8.4). 

Azete, tris-dimethylamino-, structure, calculation, synthesis, 56, 356 Azetidine carbonitrile oxides, vinyl-, intramolecular cycloadditions, 60,... 

Soil and sediment organic matter affect environmental transformation reactions through direct participation in reduction (e.g., dechlorination) and oxidation (halogenation) reactions (e.g., Svenson et al., 1989 Barkovskii and Adriaens, 1998 Fu et al., 1999 Keppler et al., 2000), or by serving as an electron acceptor for microbial respiration (Lovley et al., 1996). The latter reaction has been coupled to the microbial capability to oxidize vinyl chloride... 

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