Hydrogen telluride was found to reduce imines and enamines to the corresponding amines under mild conditions. As an application of this reduction,a new method for reductive alkylation of primary and secondary amines with ketones or aldehydes has been developed.
A generalstudy of the regioselective hydroamination of terminalalkynes in the presence of Ti(NEt 2 ) 4 and different aryloxo and alkoxoligands is presented. Depending on the ligand the regioselectivity towards the Markovnikov and the and-Markovnikov addition product can be controlled. The experimentally observed isomer distribution is explained perfectly by detailed theoretical investigations which
Controlling selectivity: from Markovnikov to anti-Markovnikov hydroamination of alkynes
作者:Annegret Tillack、Vivek Khedkar、Matthias Beller
DOI:10.1016/j.tetlet.2004.09.168
日期:2004.11
Depending on the catalyst a remarkable control of regioselectivity is achieved for the titanium-catalyzed intermolecular hydroamination of various alkynes. Proper choice of sterically hindered phenol ligands such as 1 and 4 enables a selectivity switch from the Markovnikov to the anti-Markovnikov products from M:anti-M = > 90:10 to > 10:90. (C) 2004 Elsevier Ltd. All rights reserved.
Anti-Markovnikov Hydroamination of Terminal Alkynes
作者:Annegret Tillack、Ivette Garcia Castro、Christian G. Hartung、Matthias Beller