CuBr/rac-BINOL-Catalyzed N-Arylations of Aliphatic Amines at Room Temperature

Abstract

We have developed an efficient and readily available catalyst system CuBr/racemic BINOL (1,1'-binaphthyl-2,2'-diol) that catalyzes N-arylation of aliphatic amines at room temperature, and this inexpensive catalyst system is of high selectivity and tolerance toward various functional groups in the substrates.

A Facile and Efficient Oxalyldihydrazide/Ketone‐Promoted Copper‐Catalyzed Amination of Aryl Halides in Water

“…A landmark improvement was the work of Buchwald and coworkers on the use of catalytic copper in the presence of diamino ligands. [3] Thereafter, a series of novel mono-and bidentate ligands for Cu-based C-N coupling were discovered, such as organic phosphanes, [4] N-containing aromatic heterocycles, [5] diamines, [6] diols, [7] triols, [8] rac-binol, [9] salicylamide, [10] β-diketones, [11] β-keto esters, [12] imines, [13] amino acids, [14] amino alcohols, [15] amino phosphates, [16] and diazaphospholane. [17] Among them, Buchwald introduced β-diketones as ligands, which made it possible to carry out the coupling of aryl iodides with aliphatic amines even at room temperature in organic media.…”

Copper Catalyzed Assembly of N‐Aryloxazolidinones: Synthesis of Linezolid, Tedizolid, and Rivaroxaban

“…literature precedent. [9] Application of these conditions to the pharmaceutical intermediate (8) proved successful manifesting comparable efficiency to the test substrate (Scheme 7). This granted access to linezolid in a 77 % yield with a total synthesis yield of 22 % for the final product from ethyl carbamate 3.…”

“…[%] [b] 1 [5] CuI (10 %), L1 (20 %), Cs 2 CO 3 , MeCN, 80°C, 20 h 0 2 [7] CuI (10 %), L2 (10 %), K 3 PO 4 , 1,4-dioxane, 80°C, 24 h 9 3 [8] CuI (10 %), L3 (20 %), K 2 CO 3 , DMSO, 100°C, 20 h 30 4 [9] CuBr (20 %), L4 (20 %), K 3 PO 4 , DMF, 80°C, 4 h 78 5 [9] CuI (20 %), L4 (20 %), K 3 PO 4 , DMF, 60°C, 20 h 30 [c] 6 [10] Pd(dba) 2 (5 %), L5 (10 %), NaOtBu, PhMe, 100°C, 20 h 10 Unfortunately the cyclization-arylation conditions were not tolerated in this reaction (entry 1). Pleasingly one set of conditions (entry 4) led to efficient morpholine coupling, however at elevated temperatures cf.…”

Copper‐Catalyzed Ligand Promoted Ullmann‐Type Coupling Reactions

“…Buchwald and coworkers discovered that diethylsalicylamide ( L17 ) was a suitable ligand for accelerating the reaction of aryl bromides (entry 3) [4] , which could overcome the drawback of their ethylene glycol ligand that is only suitable for aryl iodides [5] . Two powerful catalytic systems, CuI/ L20 [6,7] (entry 4) and CuBr/ L22 [8] (entry 6), which enable the coupling to proceed at room temperature, were disclosed recently. However, only some aryl iodides gave good conversion while most of the aryl halides still required higher reaction temperatures for complete reaction (entry 5).…”