Aryl derivatives with ethylene derivative

G-Alkylation of aryl derivatives with ethylene derivatives G G GHGAr... 

Phosphoric acid boron fluoride C-Alkylation of aryl derivs. with ethylene derivs. 

Ziegler catalysis involves rapid polymerization of ethylene and a-ole-fins with the aid of catalysts based on transition-element compounds, normally formed by reaction of a transition-element halide or alkoxide or alkyl or aryl derivative with a main-group element alkyl or alkyl halide (1,2). Catalysts of this type operate at low pressures (up to 30 atm), but often at 8-10 atm, and, in special cases, even under reduced pressure, and at temperatures up to 120°C, but often as low as 20-50°C. Approximately 2,200,000 tons of polyethylene and 2,900,000 tons of polypropylene are produced per year with the aid of such catalysts. The polyeth-... 

The stereochemistry observed in this reaction provides useful insights into the reaction mechanism. trans-Disubstituted ethylenes have been isolated from the reaction of aldehyde tosyUiydrazones with aryl nonallates. The reaction of aryl nonallates with tosyUiydrazones derived from dialkyl ketones mainly leads to... 

Dialkoxycarbonylation has been reported using a Pd-catalyst/oxidant system on propynols or butynols furnishing respectively /3- or y-lactone derivatives with a-(alkoxycarbonyl)ethylene chains (Scheme 24) [83,137, 138]. This reaction occurs in a stereospecific way leading exclusively to cis-dicarbonylated products in fair to excellent yields (25-97%). Noteworthy, a butynol bearing an alkyl or an aryl substituent instead of a TMS one undergoes a different course of reaction under the same conditions here frans-alkoxycarbonylation takes place selectively (Scheme 25). 

Considering functionalized olefins first, only three two-carbon reactants are listed above. Ethylene itself can give only terminal double bonds when elimination is facile and triethylamine functions as the base. If nucleophilic secondary amines are necessary, ethylene produces internal amines almost entirely. Aryl halides react well with ethylene to produce styrene derivatives. 

The final common class of coupling reactions to form C-C bonds described here is the coupling of an aryl halide with an olefin to cleave the C-H bond of the olefin and replace it with an aryl group. This reaction, which is shown generically in Equation 19.18, was first reported by Mizoroki the synthetic utility of this process and e most useful conditions for this process at the time were reported by Heck. ° This process is often called the "Heck reaction," or more appropriately the "Mizoroki-Heck reaction." " The Heck reaction is most commonly conducted with electron-deficient olefins, such as styrene or acrylate derivatives. The electronic properties of these substrates tend to favor formation of the conjugated products. The reaction can also be conducted effectively with ethylene a Heck reaction between 6-methoxy-2-bromonaphthalene and ethylene is one step of a short, catalytic commercial synthesis of naproxen. In contrast, intermolecular reactions of internal olefins typically form mixtures of regioisomeric products. Intramolecular Mizoroki-Heck reactions with intemal olefins are more common. Mizoroki-Heck reactions of aliphatic electrophiles have been reported, but remain rare. Applications of the Mizoroki-Heck reaction have been reviewed. ... 

Syntheses with palladium complexes Arylation of ethylene derivs. 

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