作者:Sarah A. Kavanagh、Alessandro Piccinini、Stephen J. Connon
DOI:10.1002/adsc.201000255
日期:2010.10.9
demonstrated for the first time that a sulfide catalyst, utilised at 20 mol% loading, can promote methylene transfer to ketones in the presence of methyl triflate and an organic base. This metal-free methodology is of broad scope – both aliphatic and aromatic ketones (including trifluoromethyl ketones) can be converted to synthetically useful terminal epoxides in excellent yields at room temperature.
Se powder as the selenating reagent, the copper-catalyzed double C–Se cross-coupling of aryl iodides, epoxides, and elemental selenium has been developed. This strategy provides a straightforward approach to the synthesis of β-hydroxy phenylselenides with excellent regioselectivity of the ring opening reaction. This process proceeds in generally good yields and is compatible with a broad range of functional
Microwave-Assisted Synthesis of N-<i>sec</i>- and N-<i>tert</i>-Alkylated Indoles
作者:Hartmut Schirok
DOI:10.1055/s-2008-1067005
日期:2008.5
A synthesis of N-substituted indoles by means of an epoxide-opening, nucleophilic aromatic substitution, and dehydration sequence is reported, which is capable of generating even N-tert alkyl substituted derivatives.
Continuous Flow Synthesis of Terminal Epoxides from Ketones Using in Situ Generated Bromomethyl Lithium
作者:Timo von Keutz、David Cantillo、C. Oliver Kappe
DOI:10.1021/acs.orglett.9b04072
日期:2019.12.20
preparation of epoxidesfrom ketones has been developed. The method is based on the carefully controlled generation of (bromomethyl)lithium (LiCH2Br) from inexpensive CH2Br2 and MeLi in a continuous flow reactor. The reaction has shown excellent selectivity for a variety of substrates, including α-chloroketones, which typically fail under classic Corey-Chaykovsky conditions. This advantage has been used to develop
Electrosynthesis of Benzolactones by Nickel-Catalyzed Carboxylation of Epoxide-Functionalized Aromatic Halides
作者:Patricia Tascedda、Elisabet Duñach
DOI:10.1055/s-2000-6486
日期:2000.2
The electrochemical, nickel-catalyzed carbon dioxide incorporation into 2-haloaryl epoxides led chemoselectively to different carboxylated products according to the nature of the substrate and to the catalytic system. Whereas terminal epoxide derivatives led to cyclic carbonates in good yields, disubstituted epoxides reacted through a first carbon-halogen bond carboxylation followed by epoxide ring opening. Five-membered ring benzolactones were selectively formed with cyclam as the ligand, whereas 6-membered ring isocoumarine derivatives were obtained using 2,2′-bipyridine.