Rhodium(III)‐Catalyzed ortho‐Alkenylation of Anilides with Maleimides

Abstract

A rhodium(III)-catalyzed ortho-alkenylation of substituted anilides with maleimides providing 3-arylated maleimides in good to excellent yields is described. In the reaction, a minor amount of Michael-type addition product, 3-arylated succinimides, was also observed. Later, 3-arylated succinimides was converted into 3-arylated maleimides in the presence of diisopropyl azodicarboxylate and K 2 CO 3 . Generally, a Michael-type 3arylated succinimides was observed in the reaction of maleimides with substituted aromatics via C-H bond activation. In the present reaction, unusually, a Heck-type alkenylated product was observed in the major amount. A possible reaction mechanism was proposed and supported by the deuterium labelling studies and computational experiments. The mechanistic investigation and DFT calculations revealed that the time interval for the regeneration of Rh(I) to Rh(III) could be the factor for the observation of a minor ortho alkylated aromatics which was formed via a redox neutral Rh(III) version.[a] Dr.

C–H Bond Alkylation of Cyclic Amides with Maleimides via a Site-Selective-Determining Six-Membered Ruthenacycle

“…White solid, yield = 91%, 160.0 mg. Mp: 167− 169 °C. 1 H NMR (400 MHz, CDCl 3 ): δ = 7.78 (d,J = 7.6 Hz,1H),7.53 (dd,J = 7.6,7.2 Hz,1H),2H),7.15 (d,J = 8.8 Hz,1H),6.86 (dd,J = 8.8,2.8 Hz,1H),6.69 (s,1H),4.76 (d,J = 17.6 Hz,1H), 4.67 (d,J = 17.2 Hz,1H), 4.00 (dd, J = 9.2, 5.6 Hz, 1H), 3.74 (s, 3H), 3.07 (dd, J = 18.8, 9.6 Hz, 1H), 2.94 (dd, J = 18.8, 4.8 Hz, 1H), 2.70 (s, 3H) ppm. 13 C{ 1 H} NMR (100 MHz, CDCl 3 ): δ = 177.7, 176.…”

“…1-Methyl-3-(5-(1-oxoisoindolin-2-yl)benzo [d][1,3]dioxol-4-yl)pyrrolidine-2,5-dione (2f). Brown solid, yield = 85%, 155.0 mg. Mp: >250 °C dec. 1 H NMR (400 MHz, CDCl 3 ): δ = 7.88 (d, J = 7.6 Hz, 1H), 7.60 (dd, J = 7.6, 7.2 Hz, 1H), 7.51 (dd, J = 8.0, 8.0 Hz, 2H), 6.85−6.78 (m, 2H), 6.00 (s, 2H), 4.79 (d,J = 17.6 Hz,2H),3.95 (dd,J = 8.8,7.2 Hz,1H),2H), 2.85 (s, 3H) ppm. 13 C{ 1 H} NMR (100 MHz, CDCl 3 ): δ = 177.…”

“…White solid, yield = 66%, 109.9 mg. Mp: 153−155 °C. 1 H NMR (400 MHz, CDCl 3 ): δ = 7.85 (d,J = 8.4 Hz,1H),7.58 (dd,J = 7.2,7.2 Hz,1H),7.49 (dd,J = 6.8,6.4 Hz,2H),7.18 (d,J = 7.6 Hz,1H),7.10 (d,J = 6.4 Hz,2H),4.86 (d,J = 17.2 Hz,1H), 4.77 (d,J = 17.2 Hz,1H), 4.06 (dd, J = 9.2, 5.2 Hz, 1H), 3.14 (dd,J = 18.8,9.6 Hz,1H), 2.98 (dd, J = 18.8, 5.2 Hz, 1H), 2.78 (s, 3H), 2.34 (s, 3H) ppm. 13 C{ 1 H} NMR (100 MHz, CDCl 3 ): δ = 178.…”

Rhodium(III)‐Catalyzed Oxidative C(sp3)−H Alkenylation of 8‐Methylquinolines with Maleimides Under Aerobic Conditions

“…For instance, Prabhu reported a carboxylate group assisted Rh(III)‐catalyzed C(sp 2 )−H activation with maleimides leading to the decarboxylative Heck‐type products . Jeganmohan's group also disclosed a Rh(III)‐catalyzed ortho‐alkenylation of anilides with maleimides providing a Heck‐type product as the main product . Sharma's group demonstrated a Rh(III)‐catalyzed C(sp 2 )‐H alkenylation of 1,4‐naphthoquinones with maleimides .…”

Transition metal-catalyzed coupling of heterocyclic alkenesviaC–H functionalization: recent trends and applications

“…Similarly, the alkenylation of acetanilides can be accomplished (Scheme 26A). 43 In addition, the carboxylate directed C-H activation/decarboxylative Hecktype coupling of benzoic acid is achieved (Scheme 26B). 44 The selectivity depends on the reaction medium.…”