The Mizoroki-Heck (MH) reaction involving aryl halides with various acrylates and acrylamides has been studied using air and moisture-stable imidazolium-based palladate precatalysts. These pre-catalysts can be converted into Pd-NHC species (NHC = N-heterocyclic carbene) under catalytic conditions and are capable of facilitating the Mizoroki-Heck reaction of aryl halides with various acrylates. The effects of solvent, catalyst loading, temperature and bases on the reaction out- [a] 4697 Scheme 2. Substrate scope for the MH reaction with acrylate 2a-b.General Procedure for the Mizoroki-Heck Reaction: In air, a vial was charged with [SIPr·H][Pd(η 3 -2-Me-allyl)Cl 2 ] (Pd-1) (4.4 mg, 1.4 mol%), K 2 CO 3 (2.0 equiv.), DMF (1 mL) and a magnetic stir bar. The corresponding aryl halide (0.5 mmol) was added followed by the corresponding acrylate (1.0 equiv.), and the vial was then sealed with a screw cap. The reaction was left to stir for 20 h at 100°C. Afterwards, distilled water (2 mL) was added and the products were extracted with diethyl ether (3 × 3 mL). Finally, the products were isolated by flash column chromatography. The isolated yields are average of two runs. All the related supporting data are given in the Supporting Information.
Mizoroki-Heck Reaction Scale Up:Following the general procedure, [SIPr·H][Pd(η 3 -2-Me-allyl)Cl 2 ] (Pd-1) (44 mg, 1.4 mol%), K 2 CO 3 (1.38 g, 2.0 equiv.), DMF (10 mL) were charged into oven dried 20 mL screwed cap vial. 4-bromoanisol (0.93 g, 5 mmol) and n-butyl acrylate (0.64 g, 5 mmol) were added subsequently and the vial was closed and heated to 100°C for 20 h. the reaction residue was purified by column chromatography 100-200 mesh silica gel and EtOAc/n-hexane (3:97) to afford 3a in 1.13 g (97%) as a yellow liquid. 1 H NMR (400 MHz, CDCl 3 ): δ (ppm) = 7.63 (d, J = 16.4 Hz, 1H, CH=CH), 7.47 (d, J = 8.8 Hz, 2HAr), 6.90 (d, J = 8.8 Hz, 2HAr), 6.31 (d, J = 16.4 Hz, 1H, CH=CH), 4.19 (t, J = 7.2 Hz, 2H, OCH 2 ), 3.84 (s, 3H, OCH 3 ), 1.64-1.70 (m, 2H , CH 2 ), 1.40-1.46 (m, 2H , CH 2 ), 0.96 (t,