New functionalized alkenylmagnesium reagents bearing an oxygen function in the β-position. Preparation and reaction of 5-magnesiated-1,3-dioxin-4-one derivatives
摘要:
5-Magnesiated-1,3-dioxin-4-ones have been prepared by performing a low temperature iodine-magnesium exchange reaction. These alkenylmagnesium reagents bearing an alkoxy function in the beta -position react directly with aldehydes or with other electrophiles such as acid chlorides, allylic bromides, aryl and alkenyl iodides in the presence of a copper or palladium transition metal catalyst. (C) 2001 Elsevier Science Ltd. All rights reserved.
Flash Flow Pyrolysis: Mimicking Flash Vacuum Pyrolysis in a High-Temperature/High-Pressure Liquid-Phase Microreactor Environment
作者:David Cantillo、Hassan Sheibani、C. Oliver Kappe
DOI:10.1021/jo3001645
日期:2012.3.2
allowing higher productivities and space–time yields compared with gas-phase protocols. Differential scanning calorimetry measurements and extensive DFT calculations provided essential information on pyrolysis energy barriers and the involved reaction mechanisms. A correlation between computed activation energies and experimental gas-phase FVP (molecule–wall collisions) and liquid-phase FFP (molecule–molecule
Reaction of α-oxoketenes with 2-substituted benzothiazoles and benzimidazoles: synthesis of benzo[4,5]thiazolo[3,2-a]pyridinone and N-(1,3-benzothiazol-2-yl)-3-oxopropanamide derivatives
作者:Mahboobeh Zahedifar、Hassan Sheibani
DOI:10.1007/s10593-016-1829-3
日期:2016.1
cyclocondensation reactions of α-oxoketenes with 2-substituted benzothiazoles have been investigated. Acyl-substituted Meldrum's acids and 1,3-dioxin-4-one derivatives have been used as starting compounds for preparation of α-oxoketenes, which were used in the cycloaddition reactions with (benzothiazol-2-yl)-acetonitrile and (benzimidazol-2-yl)acetonitrilegiving good product yields. Also the reaction of (ch
Gold-catalyzed formal [4π+2π]-cycloadditions of tert-butyl propiolates with aldehydes and ketones to form 4H-1,3-dioxine derivatives
作者:Somnath Narayan Karad、Wei-Kang Chung、Rai-Shung Liu
DOI:10.1039/c5cc04538j
日期:——
Novel gold-catalyzed [4π+2π]-cycloadditions of tert-butyl propiolates with aldehydes and ketones have been developed to form 4H-1,3-dioxine derivatives.
Versatile Synthesis of Acylfuranones by Reaction of Acylketenes with α-Hydroxy Ketones: Application to the One-Step Multicomponent Synthesis of Cadiolide B and Its Analogues
Functionalized acylfuranones have been prepared in a one-step procedure by thermal fragmentation of the corresponding dioxinones in the presence of hydroxy ketones in basic conditions. Multicomponentreactions also occur on addition of an aldehyde as a third reaction partner resulting in an expeditious access to cadiolideB and itsanalogues.
在碱性条件下,在羟基酮的存在下,通过相应的二恶英酮的热裂解,以一步法制备了官能化的酰基呋喃酮。添加醛作为第三个反应伙伴时也会发生多组分反应,从而快速获得卡地内酯 B 及其类似物。
Gold-catalyzed formal [4π + 2π]-cycloadditions of propiolate derivatives with unactivated nitriles
作者:Somnath Narayan Karad、Wei-Kang Chung、Rai-Shung Liu
DOI:10.1039/c5sc01950h
日期:——
Gold-catalyzed hetero-[4π + 2π]-cycloadditions of tert-butyl propiolates with unactivated nitriles are described. This new finding enables a one-pot gold-catalyzed synthesis of highly substituted pyridines.