Synthetic and Mechanistic Studies of Indium-Mediated Allylation of Imines in Ionic Liquids
作者:Man Chun Law、Tin Wai Cheung、Kwok-Yin Wong、Tak Hang Chan
DOI:10.1021/jo062198x
日期:2007.2.1
Aldimines derivedfrom aryl and non-enolizable aliphatic aldehydes were allylated with allyl bromide mediated by indium powder in [bpy][BF4] (bpy = N-butylpyridine) to give good yields of the corresponding homoallylic amines. Selective formation of monoallylated amines can be achieved by varying the amount of bromide ion additive in the form of [bpy][Br]. The transient organoindium intermediates, allylindium(I)
One-Pot Synthesis of<i>N</i>-Chloroacetyl 1-Aminoalkyl Phosphonates - Precursors of 4-Phosphono-β-Lactams
作者:Christian V. Stevens、Kristof Moonen
DOI:10.1055/s-2005-918440
日期:——
4-Phosphono-β-lactams are synthesized via a three-step sequence, including final formation of the C3-C4 bond through a phosphorus-stabilized carbanion. The chlorinated precursors can be synthesized via two different methods: a one-pot N-acylation of an aromatic imine followed by addition of a trialkyl phosphite or phosphonylation of a suitable imine followed by N-acylation in a separate reaction step. The former method was preferred because of the ease of the reaction and the good yields obtained.
Trichlorosilane-Dimethylformamide (Cl<sub>3</sub>SiH-DMF) as an Efficient Reducing Agent. Reduction of Aldehydes and Imines and Reductive Amination of Aldehydes under Mild Conditions Using Hypervalent Hydridosilicates
作者:Shu Kobayashi、Masaru Yasuda、Iwao Hachiya
DOI:10.1246/cl.1996.407
日期:1996.5
Trichlorosilane-dimethylformamide (Cl3SiH-DMF) was found to be an effective reducing agent for reduction of aldehydes to alcohols, imines to amines, and also reductiveamination of aldehydes. Hypervalent silicates are active species, which enable efficientreduction under mild conditions.
1,4-Butanediol as a Reducing Agent in Transfer Hydrogenation Reactions
作者:Hannah C. Maytum、Javier Francos、David J. Whatrup、Jonathan M. J. Williams
DOI:10.1002/asia.200900527
日期:2010.3.1
H2 in hydrogen‐transfer reactions to ketones, imines, and alkenes. Unlike simple alcohols, which establish equilibrium in the reduction of ketones, 1,4‐butanediol acts essentially irreversibly owing to the formation of butyrolactone, which acts as a thermodynamic sink. It is therefore not necessary to use 1,4‐butanediol in great excess in order to achieve reduction reactions. In addition, allylic alcohols
A Pd‐catalyzed carbonylation of α‐chloro ketones in the presence of imines leads to α‐alkylidene β‐oxo amides in good yields. This one‐pot synthetic method is highly stereoselective and affords amides only as (Z) isomers. This work increases the potential of Pd‐catalyzed reactions in the direct synthesis of carbonyl compounds.