33962-90-2Relevant articles and documents
Base-Mediated Borylsilylation/Silylation of Ammonium Salts with Silylborane
Du, Xian,Guan, Yun-Shi,Li, Yi-Hui,Liang, Guohai,Luo, Yong,Qi, Wan-Ying,Wang, Zi-Ying,Wei, Xun,Xu, Xiao-Hong,Yuan, Han,Zhen, Jing-Song
supporting information, p. 5988 - 5992 (2021/08/31)
This work describes a base-mediated borylsilylation of benzylic ammonium salts to synthesize geminal silylboronates bearing benzylic proton under mild reaction conditions. Deaminative silylation of aryl ammonium salts was also achieved in the presence of
Platinum-catalyzed direct amination of allylic alcohols under mild conditions: Ligand and microwave effects, substrate scope, and mechanistic study
Ohshima, Takashi,Miyamoto, Yoshiki,Ipposhi, Junji,Nakahara, Yasuhito,Utsunomiya, Masaru,Mashima, Kazushi
body text, p. 14317 - 14328 (2010/02/16)
Transition metal-catalyzed amination of allylic compounds via a π-allylmetal intermediate is a powerful and useful method for synthesizing allylamines. Direct catalytic substitution of allylic alcohols, which forms water as the sole coproduct, has recently attracted attention for its environmental and economical advantages. Here, we describe the development of a versatile direct catalytic amination of both aryl- and alkyl-substituted allylic alcohols with various amines using Pt-Xantphos and Pt-DPEphos catalyst systems, which allows for the selective synthesis of various monoallylamines, such as the biologically active compounds Naftifine and Flunarizine, in good to high yield without need for an activator. The choice of the ligand was crucial toward achieving high catalytic activity, and we demonstrated that not only the large bite-angle but also the linker oxygen atom of the Xantphos and DPEphos ligands was highly important. In addition, microwave heating dramatically affected the catalyst activity and considerably decreased the reaction time compared with conventional heating. Furthermore, several mechanistic investigations, including 1H and 31P{1H} NMR studies; isolation and characterization of several catalytic intermediates, Pt(xantphos)Cl2, Pt(η2-C3H5OH)(xantphos), etc; confirmation of the structure of [Pt(η3-allyl)(xantphos)]OTf by X-ray crystallographic analysis; and crossover experiments, suggested that formation of the π-allylplatinum complex through the elimination of water is an irreversible rate-determining step and that the other processes in the catalytic cycle are reversible, even at room temperature.
Hydride Transfer Reaction Products in the Aminomethylation of Styrene
Manninen, Kalle,Karjalainen, Aira
, p. 190 - 195 (2007/10/02)
Aminomethylation of styrene with formaldehyde and dimethylamine leads to N-methylbenzenepropanamine (1), N-(3-phenylpropyl)benzenepropanamine (3), and α-methylenebenzenepropanal (4) as major products.The ratio of 1, 3 and 4 is considerably influenced by the ratio of the reactants.The best yield of 1 is obtained by using dimethylamine in excess.Styrene in excess favors the formation of 3, and equivalent amounts of reactants afford the best yield of 4.Using formaldehyde in excess leads to the complete N-methylation of 1 and 3.When styrene reacts with formaldehyde and diethylamine or diisopropylamine the most important aminomethylation products are N-ethylbenzenepropanamine (11) or N-isopropylbenzenepropanamine (12), respectively, and 3 and 4 in both cases.The formation of the major products in the aminomethylation of styrene can be explained by the hydride transfer mechanism represented earlier as one competing mechanism for the aminomethylation of certain bicyclic alkenes.The N-methylation of amine 1 and 3, when formaldehyde is used in excess, is due to Eschweiler methylation under aminomethylation conditions.
