Palladium-Catalyzed Decarboxylative sp³−sp³ Coupling of Nitrobenzene Acetic Esters

Abstract

Allylic esters of nitrobenzene acetic acids undergo facile palladium-catalyzed decarboxylative coupling. Both mono-and dinitroarene substrates give high yields of the coupled products. Moreover, the rates of the reactions suggest that decarboxylation is rate-limiting and substrates that sterically disfavor attainment of the reactive conformation for decarboxylation are not viable. Finally, reduction of the product nitroarenes to the corresponding anilines provides access to a variety of heterocycles including quinolines and dihydroquinolones.

A Highly Efficient Palladium‐Catalyzed Decarboxylative ortho‐Acylation of Azobenzenes with α‐Oxocarboxylic Acids: Direct Access to Acylated Azo Compounds

“…Since then, significant progress has been made on decarboxylative cross‐coupling reactions 3. For example, Goossen,3a–d Forgione,3e Li,3f Liu,3g,h Miura,3i Lee,3j and Tunge3k,l have studied decarboxylative biaryl coupling, olefination, alkynylation, aryl ketone formation and so forth. Very recently, Ge,4 Duan,5 Kim,6 Tan,7 Zhu,8 and Saxena9 have further demonstrated the feasiblity of decarboxylative acylation of arenes and other substrates by Pd‐catalyzed group‐directed CH activation.…”

Photokatalyse mit sichtbarem Licht: Welche Bedeutung hat sie für die organische Synthese?

“…[188] Neben den Ni-Katalysatoren kann auch Palladium als Cokatalysator in photokatalytischen Reaktionen eingesetzt werden. [190] [190] …”

“…Nach dem Beispiel der Tsuji-Trost-Allylierung,d e- [189] Die milden Reaktionsbedingungen und kein Zusatz von aktivierenden Reagenzien macht die photokatalytische Va riante gut vergleichbar mit klassischen palladiumkatalysierten, benzylischen Allylierungensprozessen. [190]…”

Transition Metal-Catalyzed Decarboxylative Allylation and Benzylation Reactions

“…While the majority of synthetic efforts have focused on the decarboxylative allylation of enolates, DcA has proven to be a rather general method for in situ formation of a number of carbon nucleophiles including: acetylides, 15 α-cyano anions, 15 acrylonitriles, 15 coumarins, 82 nitronates, 18 heteroaromatic alkanes, 83 nitrotolyl anions, 84 α-ketimine anions, 85 and α-sulfonyl anions. 86 In addition to the carbon nucleophiles generated via decarboxylation, heteroatom nucleophiles have also been shown to participate in DcA reactions and will be discussed in a later section.…”