Hybrid Metal/Organo Relay Catalysis Enables Enynes To Be Latent Dienes for Asymmetric Diels–Alder Reaction
作者:Zhi-Yong Han、Dian-Feng Chen、Ya-Yi Wang、Rui Guo、Pu-Sheng Wang、Chao Wang、Liu-Zhu Gong
DOI:10.1021/ja3007148
日期:2012.4.18
to serve as latent 1,3-silyloxydienes capable of participating in the first cascadehydrosiloxylation of an enynyl silanol/asymmetric Diels-Alder reaction. A variety of polycyclic compounds bearing multistereogenic centers were obtained in high yields and excellent enantioselectivities from the relaycatalyticcascadereaction between (2-(but-3-en-1-ynyl)phenyl) silanols and quinones catalyzed by the
Alkenyl Bromides by Brominative Deoxygenation of Ketones in One or Two Steps
作者:Ulrich Von Roman、Jakob Ruhdorfer、Rudolf Knorr
DOI:10.1055/s-1993-25986
日期:——
The conversion of ketones into alkenyl bromides is accomplished in one or two steps by 2,2,2-tribromo-2,2-dihydro-1,3,2-benzodioxaphosphole or by the dibromomethyl methyl ether prepared therefrom. Investigations of the scope and limitations provide some hints for the preparative planning and improvement.
[EN] FE/CU-MEDIATED KETONE SYNTHESIS<br/>[FR] SYNTHÈSE DE CÉTONE MÉDIÉE PAR FE/CU
申请人:HARVARD COLLEGE
公开号:WO2019009956A1
公开(公告)日:2019-01-10
Provided herein are methods for preparing ketone-containing organic molecules. The methods are based on novel iron/copper-mediated ("Fe/Cu-mediated") coupling reactions. The Fe/Cu-mediated coupling reaction can be used in the preparation of complex molecules, such as halichondrins and analogs thereof. In particular, the Fe/Cu-mediated ketolization reactions described herein are useful in the preparation of intermediates en route to halichondrins.
Rapid access to highly functionalized alkylidene cyclohexanols through a one-pot desymmetrizing hydroformylation/carbonyl enecyclization starting from simple bisalkenylcarbinols is reported. Mechanistic insight into the carbonyl ene reaction is given, highlighting the importance of hyperconjugative substituent effects.
A stereoselective approach to dienylamines is described, starting from enantiomerically enriched stannylated allylamines, which are in turn derived fromaminoacids. Conveniently the procedure allows to introduce diversity at 1-,2- and 4- positions of the final compounds. Conversion to vinylstannane has been extended to dipeptido aldehydes. The possible elaboration of 4-methyl substituted dienylamines