Aryl-alkenyl coupling reactions

A. Aryl-Aryl, Aryl-Alkenyl and Alkenyl-Aryl Coupling Reactions. 483... 

Some of the notable recent developments in the Pd- or Ni-catalyzed aryl-alkenyl and alkenyl-aryl coupling reactions include the use of aryl and alkenyl chlorides along the lines of earlier discussions. lust a couple of representative examples of the aryl-alkenyl coupling reaction with alkenyl chlorides are shown in Scheme 33. 

The Pd-catalyzed aryl-alkenyl and alkenyl-aryl coupling reactions involving Zn, A1 and Zr have been applied to the syntheses of a fair number of natural products26. Recent examples published in the last several years include the syntheses of UB-165107 and (—)-diazonamide A108 (Scheme 35). 

Mechanism The Pd- or Ni-catalyzed alkenyl-alkenyl and alkenyl-aryl coupling reactions may proceed according to Scheme 5.25, involving the oxidative addition, transmetallation and reductive elimination. 

Arylmetals can be coupled with alkenyl and alkynyl halides. In these cases, the reverse polarity affinity patterns, i.e., the alkenyl-aryl and alkynyl-aryl coupling reactions... 

Hydrometallation-cross-coupling and carbometallation-cross-coupling tandem protocols and other alkenyl-aryl, alkenyl-alkenyl, and alkenyl-alkynyl coupling reactions double metal catalysis... 

Negishi, E., Baba, S. Novel stereoselective alkenyl-aryl coupling via nickel-catalyzed reaction of alkenylalanes with aryl halides. J. Chem. Soc., Chem, Commun, 1976, 596-597. 

The synthesis of alkene-substituted arenes by cross-coupling can, in principle, be achieved either by the reaction of alkenyhnetals with aryl halides and related electrophiles or by that of arylmetals with alkenyl electrophiles. For the sake of simplicity, the former reaction is termed the alkenyl-aryl coupling, while the latter is termed the aryl-alkenyl coupling in this Handbook. Similar terms may be devised by linking the carbon groups of the organometal and organic electrophile with a dash in this order. 

Scheme 3.48 Synthesis of allylarenes by Pd-catalyzed allyl-aryl, aryl-allyl, benzyl-alkenyl, and alkenyl-benzyl coupling reactions.

Scheme 5-76. Aryl-alkenyl cross-coupling reactions involving zinc organometallics. ...

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