Palladium-Catalyzed Intermolecular Coupling of Aryl Halides and Amides

Abstract

[formula: see text] The first general intermolecular C-N bond-forming reactions between aryl halides and amides were realized using a palladium catalyst with Xantphos as the ligand. Aryl triflates, carbamates, and sulfonamides are also viable substrates for the amidations, which proceed at 45-110 degrees C with 1-4 mol% of Pd catalyst in 66-99% yields and exhibit good functional group compatibility.

Microwave Assisted, Solvent- and Ligand-Free Copper Catalyzed N-Arylation of Phenylurea with Aryl Halides

“…We then used potassium phosphate tribase (K 3 PO 4 ·H 2 O) instead of potassium tertiary butoxide for the reaction as several reports described the use of K 3 PO 4 in C-N coupling reactions. 7 The yields were decreased when 1 equiv of K 3 PO 4 was used (Table 1, entries 4 and 13). The reactions were quite convenient as only 20 min of microwave irradiation was required for 1 mmol scale reaction.…”

“…Even more recent expansions in the scope of this method allowed one to perform arylation of amides, 6-9 sulfonamides 7,8 and ureas 10 under rather mild conditions tolerating various functional groups. One of the most powerful ligands used in such palladium-catalyzed reactions is Xantphos.…”

“…One of the most powerful ligands used in such palladium-catalyzed reactions is Xantphos. [7][8][9][10] However, the utility of this ligand is mainly limited to the amidation of electrondeficient aryl halides. Reactions with unactivated aryl halides usually require higher catalyst loadings and give much lower product yields.…”

“…Reactions with unactivated aryl halides usually require higher catalyst loadings and give much lower product yields. [7][8][9][10] In many cases, especially when an electron donating group like methoxy is present in the aryl halide, the reaction fails. 7,9 Recently, Nandakumar reported a copper catalyst system for the amidation of aryl halides with urea.…”

N-Benzoyl-N-methylsulfonyl anthranilates: unexpected cyclization reaction to 4-alkoxy-2,1-benzothiazines

“…In order to evaluate the reaction reproducibility and to exclude any influence of the 2-bromophenoxy substituent on the reaction trend, the cyclization was repeated using both unsubstituted methyl and ethyl N-benzoyl-N-(methylsulfonyl)anthranilate, 6a and 6b respectively; again 4-alkoxy 2,1-benzothiazines 8a (36%) and 8b (33%) were obtained together with N-benzoylanthranilate 10a 10 (20%) and 10b…”