Alkenyl aromatics

Similarly, ketimines (benzylimines of aromatic ketones) undergo the rhodium-catalyzed ortho-alkenylation with alkynes to give or/ o-alkenylated aromatic ketones after hydrolysis.61 This method is applied to an efficient one-pot synthesis of isoquinoline derivatives by using aromatic ketones, benzylamine, and alkynes under Rh catalysis (Equation (55)). 

Base-catalyzed leactions of hydrocarbons have been until recently limited to hydrocarbons having conjugated double bonds or double bonds that may be brought into conjugation, to alkenyl-aromatics, and to hydrocarbons possessing triple bonds ( ). Double-bond shifts of such compounds can occur at about 160° with such bases as alcoholic potassium hydroxide. 

Y.-C. Sun, Method for the preparation of alkenyl aromatic monomer nitrile copolymer reinforced with rubbery copolymer, US Patent 4387179, assigned to The Dow Chemical Company (Midland, MI), June 7,1983. 

Dr L.Deffet, Bruxelles private communication, March 10,1954 Alkenyl Aromatics of the general formula Ar. CH, CHa. C CH2, were prepd by reacting aruEliatic nyuiocarbons (at moderate temp and press) with 1,3 diolefins in the presence of a catalyst(such as boron trihalide satd with an organic carboxylic acid). The purified alkenyl aromatics can be nitrated to yield expl derivs... 

This simple protocol for the preparation of carboxylic acids was also successfully applied to carbonylation of alkenyl and aryl bromides under the same reaction conditions [88]. The reaction of aryl halides (including heteroaromatics, e.g., halothiophenes) with methyl acrylate, phenyl vinyl sulfone, cy-clopentene, and dihydrofuran, proceeded smoothly in water using the same PS-PEG-supported catalyst to give the corresponding alkenylated aromatics in high yields [88,89]. 

J. M. Joyce and D. J. Kelley. Polyphenylene ether-alkenyl aromatic polymer blends having organobromine additives. US Patent 4927 858, assigned to Huntsman Chemical Corporation (Salt Lake City, UT), May 22,1990. 

Table III presents data on coking tendencies of by-product liquids from gas oil pyrolysis. The data show that the pyrolysis gasoline is the most reactive of the components with significant formation of deposits at a temperature of 177 C. The gas oil, which contains fewer diolefins and alkenyl aromatics than the gasoline, is more stable and may be viewed as a diluent for the gasoline i.e., the blend of pyrolysis gasoline and gas oil can be processed at a higher temperature than the gasoline alone.

The traditional transformations towards aryl nitriles usually require harsh conditions. One of the groundbreaking researches in the direct transformation of alkenes to nitriles was reported by Denton et al. in 1950 (Scheme 4.12) [98]. In this alumna supported molybdic oxide catalyzed ammoxidation, alkyl and alkenyl aromatic hydrocarbons were converted to aromatic nitriles at high temperatures (524-552 °C). 

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