Dibromomethane as one-carbon source in organic synthesis: microwave-accelerated α-methylenation of ketones with dibromomethane and diethylamine
摘要:
The reactivity of aryl alkyl ketone with a preheated mixture of dibromomethane and diethylamine is poor and gives an alpha-methylenation product in very low yield even under refluxing condition. It can be accelerated dramatically by microwave irradiation. Under microwave condition, the cyclic 1,3-dicarbonyls, aryl alkyl ketones, heteroaryl alkyl ketones and acyclic benzyl ketone give alpha-methylenation products in modest to good yields. (C) 2003 Elsevier Science Ltd. All rights reserved.
The enantioselective synthesis of tetracyclic methyllycaconitine analogues
作者:Kevin Sparrow、David Barker、Margaret A. Brimble
DOI:10.1016/j.tet.2011.08.026
日期:2011.10
A new enantioselective synthesis of ABEF ring analogues of methyllycaconitine has been developed using a chiral cobalt(III) salen-catalyzed Diels-Alder reaction to form the B ring. Subsequent elaboration to form the A, E and F rings was achieved by sequential Dieckmann, Mannich and Wacker-type cyclizations to afford tetracyclic analogues in 97.5% ee. (C) 2011 Elsevier Ltd. All rights reserved.
Dibromomethane as one-carbon source in organic synthesis: microwave-accelerated α-methylenation of ketones with dibromomethane and diethylamine
The reactivity of aryl alkyl ketone with a preheated mixture of dibromomethane and diethylamine is poor and gives an alpha-methylenation product in very low yield even under refluxing condition. It can be accelerated dramatically by microwave irradiation. Under microwave condition, the cyclic 1,3-dicarbonyls, aryl alkyl ketones, heteroaryl alkyl ketones and acyclic benzyl ketone give alpha-methylenation products in modest to good yields. (C) 2003 Elsevier Science Ltd. All rights reserved.
Total Synthesis of Sinensilactam A
作者:Wenbin Shao、Jun Huang、Kai Guo、Jianxian Gong、Zhen Yang
DOI:10.1021/acs.orglett.8b00380
日期:2018.4.6
the in situ generated N-acyliminium intermediate with aldehyde 20. This enabled implementation of a unified strategy for stereoselective formation of the tetracyclic hemiaminal core of sinensilactam A in a later stage. The total syntheses of applanatumol F and C8-epi-applanatumol D are also achieved using this strategy.