Palladium‐Catalyzed Heck‐Type Reactions of Allylic Esters with Arylboronic Acids or Potassium Aryltrifluoroborates

Abstract

A selective and general route to (E)‐1,3‐diaryl‐prop‐1‐enes and (E)‐3‐arylallyl acetates has been developed by palladium‐catalyzed Heck‐type reactions of allylic esters with arylboronic acids or potassium aryltrifluoroborates. The present method selectively proceeds including β‐OAc elimination or β‐H elimination on the basis of the boronic acids. Whereas a variety of allylic esters were reacted with arylboronic acids, palladium(II) acetate [Pd(OAc)2], tetra(n‐butyl)ammonium chloride [(n‐Bu)4NCl] and postassium dihydrogen phosphate (KH2PO4) to afford the corresponding diarylation products in moderate to good yields, treatment of allylic esters with potassium aryltrifluoroborates furnished the corresponding monoarylation products.

Hydrazone–Palladium-Catalyzed Allylic Arylation of Cinnamyloxyphenylboronic Acid Pinacol Esters

“…The synthesis of 1,3-diarylpropene derivatives via palladium-catalyzed allylic arylation using allylic bromides or vinyl epoxides with arylboronic acids were reported as pioneering studies. Recently, palladium-catalyzed allylic arylations of allylic acetates with arylboronic acids for synthesis of 1,3-diarylpropene derivatives have been reported . Although allylic C–H arylation of allylbenzenes were also reported, Heck-type allylic C–H arylation with arylboronic acids gave the mixture of the double-bond-migrated isomers. , On the other hand, we demonstrated that easily prepared and air-stable hydrazones are effective ligands for palladium-catalyzed C–C bond formation reactions including the allylic arylation of allylic acetates with arylboronic acids .…”

Rhodium Porphyrin Catalyzed Regioselective Hydrogenolysis of 1,2-Diarylcyclopropanes with Water as the Hydrogen Source

“…The reaction with 1e (33.0 mg, 0.1 mmol) was heated in air at 200 °C for 34 h to afford 1,3-bis­(4-trifluoromethylphenyl)­propane ( 2e ; 0.056 mmol) in 56% yield and 1,3-bis­(4-trifluoromethylphenyl)­propene ( 3e ; 0.016 mmol) in 16% yield. Data for 2e are as follows.…”

“…In 96 h, 1,3-diphenylpropane (2b; 0.044 mmol) and 1,3-diphenylpropene (3b; 0.014 mmol) were obtained in 44% and 14% yields, respectively, using naphthalene as the internal standard. 1,3-Diphenylpropane: t R = 7.09; EIMS m/z (rel %) 196 (35), 105 (45), 104 (12), 103 (10), 93 (8), 92 (100), 91 (57), 79 (14), 78 (7), 77 (18), 65 (17), 51 (7). 1,3-Diphenylpropene: t R = 7.43; EIMS m/z (rel %) 194 (90), 193 (52), 179 (10), 178 (16), 117 (22), 116 (67), 115 (100), 103 (19), 91 (38), 89 (6), 77 (12), 65 (20), 63 (7), 51 (9).…”

Substrate-Directed Heck–Matsuda Arylations

“…19 In this context, the Heck arylation can be considered a privileged reaction for the formation of such esters in a regio-and stereoselective way. [20][21][22] Faced with this scenario, we decided to investigate the Heck arylation of allylic esters with diazonium salts to make it a more practical transformation. A glimpse of the most general methodologies for the E-selective g-arylation of allylic esters is shown in Table 3.…”