Palladium‐catalyzed three‐component cyclization of 2‐bromocyclohex‐1‐enecarboxylic acids with carbon monoxide and arylhydrazines leading to 2‐anilinohydroisoindoline‐1,3‐diones

Abstract

Bromocyclohex-1-enecarboxylic acids are carbonylatively cyclized with arylhydrazines or their hydrochlorides in tetrahydrofuran at 120°C under carbon monoxide pressure in the presence of a catalytic amount of PdCl 2 and 1,3-bis(diphenylphosphino) propane along with Et 3 N to give 2-anilinohydroisoindoline-1,3-diones.

Pd‐catalyzed Three‐component Cross‐coupling of Arylhydrazides with Arylboronic Acids and TFBen: Facile Access to Diaryl Ketones via Denitrogenative Carbonylation

“…In an subsequent attempt, catalytic amounts (5 mol %) of different palladium salts were checked, Pd(TFA) 2 , Pd(OAc) 2 , and Pd(MeCN) 2 Cl 2 provide 1c in 57 %, 63 %, and 83 % yield, respectively (Table 1, entries 12-14). To modulate the catalytic activity of other palladium catalysts, PdCl 2 (dppp) (dppp: [1,1'-Bis(diphenylphosphino)ferrocene]) and PdCl 2 (dppe) [dppe: 1,2-bis(diphenylphosphino)ethane)] were used, but the yield of benzophenone did not increase (Table 1, entries [15][16].…”

“…Subsequently, Wu et al [15] reported palladium-catalyzed synthesis of phthalazinones by efficient carbonylative coupling of 2-bromobenzaldehydes and hydrazines. In 2015, Cho's group [16] reported palladium-catalyzed three-component cyclization of 2-bromocyclohex-1-enecarbox-ylic acids with carbonmonoxide and arylhydrazines give 2anilinohydroisoindoline-1,3-diones. In the following year, Perrone et al [17] developed palladium-catalyzed carbonylative coupling of α-chloroketones with hydrazines as a simple route to pyrazolone derivatives.…”