meta‐C−H Arylation and Alkylation of Benzylsulfonamide Enabled by a Palladium(II)/Isoquinoline Catalyst

Abstract

Palladium(II)-catalyzed meta-C À Ha rylation and alkylation of benzylsulfonamide using 2-carbomethoxynorbornene (NBE-CO 2 Me) as atransient mediator are realized by using anewly developed electron-deficient directing group and isoquinoline as aligand. This protocol features broad substrate scope and excellent functional-group tolerance.T he metasubstituted benyzlsulfonamides can be readily transformed into sodium sulfonates,s ulfonate esters,a nd sulfonamides,a s well as styrenes by Julia-type olefination. The unique impact of the isoquinoline ligand underscores the importance of subtle matching between ligands and the directing groups. Angewandte ChemieCommunications 8185

Transient Directing Groups for Transformative C–H Activation by Synergistic Metal Catalysis

“…98 Here, a cocktail of acetates containing LiOAc$2H 2 O, CsOAc, as well as Cu(OAc) 2 $H 2 O, and AsPh 3 as the optimal ligand were found to be crucial to obtain satisfactory product yields. The powerful palladium(II)/norbornene-catalyzed meta-selective C-H activation process could be further extended to benzylsulfonamides 99 and benzylic alcohols 100 by Yu and co-workers and Ferreira and coworkers, respectively.…”

Traditional and sustainable approaches for the construction of C–C bonds by harnessing C–H arylation

“…The native functional group -COOH itself acted as the directing group, which directs the metal to ortho- C–H of arene, NBE-CO 2 Me acting as a transient mediator, relayed this ortho -cyclopalladation to meta- C–H of the arene. In the same year, Yu group also reported ligand-enabled meta -C–H arylation of benzene sulfonamides 43 (Fig. 3A, v ).…”

One-Pot Protocol To Synthesize 2-Aminophenols from Anilines via Palladium-Catalyzed C–H Acetoxylation

“…6.82 (dd, J = 8.1, 1.7 Hz, 1H), 6.40 (d, J = 8.1 Hz, 1H), 4.69 (brs, 2H). 13 + ([M + H] + ), 352.9880; found, 352.9876. 2,4-difluoro-6-((5-nitropyrimidin-2-yl)amino) Phenylacetate (2k).…”

“…NMR spectroscopy: 1 H NMR (300 MHz, CDCl 3 ,25 °C, δ): 9.25 (s, 2 H), 8.16 (dt, J = 2.4 Hz, 10.7 Hz, 1 H), 7.82 (s, 1 H), 6.77−6.69 (m, 1 H), 2.44 (s, 3 H). 13 + ([M + H] + ), 311.0586; found, 311.0574. 19 F NMR (75 MHz, CDCl 3 , 25 °C,δ): −110.9, −122.8.…”