Late‐Stage Heteroarylation of Hetero(aryl)sulfonium Salts Activated by α‐Amino Alkyl Radicals
作者:Eva Maria Alvarez、Teresa Karl、Florian Berger、Luca Torkowski、Tobias Ritter
DOI:10.1002/anie.202103085
日期:2021.6.7
We report a late-stage heteroarylation of arylsulfoniumsalts through activation with α-amino alkyl radicals in a mechanistically distinct approach from previously reported halogen-atom transfer (XAT). The new mode of activation of arylsulfoniumsalts proceeds in the absence of light and photoredox catalysts, engaging a wide range of hetarenes. Furthermore, we demonstrate the applicability of this
Cetyltrimethylammonium Bromide as an Efficient Catalyst for Regioselective Bromination of Alkoxy Naphthalenes with Trimethyl Benzyl Ammonium Tribromide: Synthetic and Kinetic Approach
作者:K. Rajendar Reddy、K. C. Rajanna、K. Uppalaiah、S. Ramgopal
DOI:10.1002/kin.20821
日期:2014.1
Bromination of 2‐alkoxynaphthalene (2‐ANP) and its derivatives with trimethylbenzylammonium tribromide (TMBATB) did not proceed smoothly even under reflux conditions. But the addition of microconcentrations of cetyltrimethyl ammonium bromide (CTAB) to the reaction afforded dramatic rate accelerations as well as good‐to‐excellent yield of the products ranging from 70% to 90%. Reactions underwent regioselective
reaction of 1-alkoxynaphthalenes 1 with alumina-supported copper(II) bromide or copper(II) chloride gave dimers, 4,4′-dialkoxy-1,1′-binaphthyls 3, as major products, and with Kieselguhr-supported copper(II) bromide afforded 1-bromo-4-alkoxynaphthalenes 2, while the reaction of 2-alkoxynaphthalenes 4 with alumina- or Kieselguhr-supported copper(II) bromide gave preferentially 1-bromo-2-alkoxynaphthalenes
1-烷氧基萘 1 与氧化铝负载的溴化铜 (II) 或氯化铜 (II) 反应生成二聚体 4,4'-二烷氧基-1,1'-联萘 3,作为主要产物,并与硅藻土负载的铜反应(II) 溴化物得到 1-bromo-4-alkoxynaphthalenes 2,而 2-alkoxynaphthalenes 4 与氧化铝或硅藻土负载的溴化铜 (II) 反应优先得到 1-bromo-2-alkoxynaphthalenes 5。
Wilson; Ma; T'ien, Journal of the Chinese Chemical Society (Peking), 1933, vol. 1, p. 11,13