Chan–Evans–Lam Amination of Boronic Acid Pinacol (BPin) Esters: Overcoming the Aryl Amine Problem
作者:Julien C. Vantourout、Robert P. Law、Albert Isidro-Llobet、Stephen J. Atkinson、Allan J. B. Watson
DOI:10.1021/acs.joc.6b00466
日期:2016.5.6
The Chan–Evans–Lam reaction is a valuable C–N bond forming process. However, aryl boronic acidpinacol (BPin) ester reagents can be difficult coupling partners that often deliver low yields, in particular in reactions with aryl amines. Herein, we report effective reaction conditions for the Chan–Evans–Lam amination of aryl BPin with alkyl and aryl amines. A mixed MeCN/EtOH solvent system was found
Cobalt(II) Phthalocyanine-Catalyzed Highly Chemoselective Reductive Amination of Carbonyl Compounds in a Green Solvent
作者:Vishal Kumar、Upendra Sharma、Praveen K. Verma、Neeraj Kumar、Bikram Singh
DOI:10.1002/adsc.201100645
日期:2012.3.16
Cobalt phthalocyanine has been employed for the highlychemoselectivereductiveamination of aldehydes and ketones in ethanol as a greensolvent. A large range of functional groups such as nitro, acid, amide, ester, nitrile, halogen, lactone, methoxy, hydroxy, alkene, N‐benzyl, O‐benzyl and heterocyclic rings were well tolerated under the present reaction conditions.
Direct reductive amination of carbonyl compounds using bis(triphenylphosphine) copper(I) tetrahydroborate
作者:Mayur J. Bhanushali、Nitin S. Nandurkar、Malhari D. Bhor、Bhalchandra M. Bhanage
DOI:10.1016/j.tetlet.2006.12.037
日期:2007.2
A direct reductive amination protocol for aldehydes/ketones using bis(triphenylphosphine) copper(I) tetrahydroborate as a novel reducing agent in the presence of sulfamic acid has been developed. The reagent chemoselectively reduces the imine moiety and does not affect other reducible functionalities such as chloro, nitro, cyano and methoxy.
Palladium-Catalyzed Formal Cross-Coupling of Diaryl Ethers with Amines: Slicing the 4-<i>O</i>
-5 Linkage in Lignin Models
作者:Huiying Zeng、Dawei Cao、Zihang Qiu、Chao-Jun Li
DOI:10.1002/anie.201712211
日期:2018.3.26
ether bonds (α‐O‐4, β‐O‐4, and 4‐O‐5 linkages) and other C−C bonds. Among the ether bonds, the bond dissociation energy of the 4‐O‐5 linkage is the highest and the most challenging to cleave. To date, 4‐O‐5 ether linkage model compounds have been cleaved to obtain phenol, cyclohexane, cyclohexanone, and cyclohexanol. The first example of direct formal cross‐coupling of diaryl ether 4‐O‐5 linkage models
Reductivealkylation of aromaticamines with 2-methoxypropene using 1.0 equivalent of HOAc and NaBH(OAc)3 in 1,2-dichloroethane (DCE) at room temperature furnished N-isopropyl amines in 50-98% yields. This method was successfully extended to trimethylsilyl enol ethers. The mild reaction conditions provide a new alternative procedure for the reductive amination of electron deficient aromatic amines