New synthesis of benzo[b]furan and indole derivatives from 1,1-dibromo-1-alkenes using a tandem Pd-assisted cyclization–coupling reaction

External oxidant-free cross-coupling: electrochemically induced aromatic C–H phosphonation of azoles with dialkyl-H-phosphonates under silver catalysis

“…The method of obtaining 2-diethyl-indol-2-ylphosphonate by the cross-coupling of dibromovinyl-ortho-aminobenzole with diethylphosphite in the presence of palladium salts was described (Scheme 1, eqn (2)). 11 Li proposed the method of direct catalytic oxidative phosphorylation of aromatic azoles in the absence of bases and acids with palladium salts as catalysts and an excess of oxidant K 2 S 2 O 8 (Scheme 1, eqn (3)). The reaction proceeds slowly at 100°C; the yields of the C-2 phosphorylated derivatives of azoles are 40-70%.…”

Synthesis of Biaryls via Palladium‐Catalyzed [2+2+2] Cocyclization of Arynes and Diynes: Application to the Synthesis of Arylnaphthalene Lignans

“…To a solution of 1-(2,2-dibromovinyl)-2-(methoxymethoxy)-benzene [23] (4.29 g, 13.3 mmol) in THF (44 mL) was added BuLi (1.47 M hexane solution, 27.2 mL, 40 mmol) at À78 8C, and the mixture was stirred at the same temperature for 10 min. To the solution was added methyl chloroformate (3.1 mL, 40 mmol) at À78 8C, and the mixture was stirred at 0 8C for 1.5 h. To the mixture was added saturated aqueous NH 4 Cl solution, and the mixture was extracted with AcOEt.…”

Silver‐Catalyzed Direct C${{_{sp{^{2}}}}}$H Phosphorylation of Indoles Leading to Phosphoindoles

“…[6] In 2004, Bisseretr eported ap alladium-assisted reaction of o- (2,2-dibromovinyl)aniline with dialkyl phosphite to afford 2-phosphoindoles. [7] Thereafter, Oshima developed ap alladium-catalyzed annulation of 1-alkynylphosphine sulfidesw ith 2-iodoanilines to afford2-phosphoindoles. [8] Indoles are widelya vailable,a nd so the direct C sp 2 À Hp hosphorylation wouldr epresent ap owerful strategy for the synthesis of different types of phosphoindoles.A lthough great progress has been made in the direct indole C sp 2 À Hf unctionalization towards forming C À C, C À O, C À Bb onds, [9 ] and direct phosphorylation of (hetero)arenes, [10] the direct indole C sp 2 À H phosphorylation stillr emains ac hallenge.…”