3598-75-2Relevant academic research and scientific papers
Dehydrogenative synthesis of imines from alcohols and amines catalyzed by a ruthenium N-heterocyclic carbene complex
Maggi, Agnese,Madsen, Robert
experimental part, p. 451 - 455 (2012/04/23)
A new method for the direct synthesis of imines from alcohols and amines is described where hydrogen gas is liberated. The reaction is catalyzed by the ruthenium N-heterocyclic carbene complex [RuCl2(IiPr)(p-cymene)] in the presence of the ligand DABCO and molecular sieves. The imination can be applied to a variety of primary alcohols and amines and can be combined with a subsequent addition reaction. A deuterium labeling experiment indicates that the catalytically active species is a ruthenium dihydride. The reaction is believed to proceed by initial dehydrogenation of the alcohol to the aldehyde, which stays coordinated to ruthenium. Nucleophilic attack of the amine affords the hemiaminal, which is released from ruthenium and converted into the imine.
Reductive amination using ammonia borane
Veeraraghavan Ramachandran,Gagare, Pravin D.,Sakavuyi, Kaumba,Clark, Paul
experimental part, p. 3167 - 3169 (2010/08/05)
A variety of primary, secondary, and tertiary amines were prepared in 84-95% yields using ammonia borane for the reductive amination of aldehydes and ketones in the presence of titanium isopropoxide.
Ruthenium-catalyzed synthesis of secondary alkylamines: Selective alkylation with aliphatic amines
Baehn, Sebastian,Hollmann, Dirk,Tillack, Annegret,Bellera, Matthias
supporting information; experimental part, p. 2099 - 2103 (2009/08/14)
The chemoselective N-alkylation of tert-alkylamines applying aliphatic amines is described for the first time. In the presence of the Shvo catalyst 1, tert-octylamine 4 and 1-adamantylamine 5 are alkylated using primary, secondary, and even tertiary amine
Cesium effect: High chemoselectivity in direct N-alkylation of amines
Salvatore, Ralph Nicholas,Nagle, Advait S.,Kyung, Woon Jung
, p. 674 - 683 (2007/10/03)
A novel method for the mono-N-alkylation of primary amines, diamines, and polyamines was developed using cesium bases in order to prepare secondary amines efficiently. A cesium base not only promoted alkylation of primary amines but also suppressed overalkylations of the produced secondary amines. Various amines, alkyl bromides, and alkyl sulfonates were examined, and the results demonstrated this methodology was highly chemoselective to favor mono-N-alkylation over dialkylation. In particular, use of either sterically demanding substrates or amino acid derivatives afforded the secondary amines exclusively, offering wide applications in peptidomimetic syntheses.
Cesium Hydroxide Promoted Chemoselective N-Alkylation for the Generally Efficient Synthesis of Secondary Amines
Salvatore, Ralph N.,Nagle, Advait S.,Schmidt, Shaun E.,Jung, Kyung Woon
, p. 1893 - 1896 (2008/02/11)
(Matrix presented) Selective N-alkylation of primary amines was developed using cesium hydroxide to prepare various secondary amines efficiently. A cesium base not only promoted monoalkylations of primary amines but also suppressed overalkylations. Various amines and alkyl bromides were examined, and the preliminary results demonstrated this methodology was highly chemoselective, favoring mono-N-alkylation over dialkylation. In particular, use of amino acid derivatives afforded the desired secondary amines exclusively.
