Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate

The mechanism of the reaction between amines with dimethyl carbonate (DMC) has been investigated. Whereas in the absence of bases, they give methylation and carboxymethylation reactions without selectivity (BAl2 and B Ac2 mechanisms, respectively), in the presence of bases, the B Ac2 mechanism preva...

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Detalles Bibliográficos
Autores principales: Tundo, Pietro, Bressanello, Salima, Loris, Alessandro, Sathicq, Ángel Gabriel
Formato: Articulo
Lenguaje:Inglés
Publicado: 2005
Materias:
Química
Amines
Carbamates
Dimethyl carbonate
Green chemistry
N-methylamines
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/83369
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-83369
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Química
Amines
Carbamates
Dimethyl carbonate
Green chemistry
N-methylamines
spellingShingle Química
Amines
Carbamates
Dimethyl carbonate
Green chemistry
N-methylamines
Tundo, Pietro
Bressanello, Salima
Loris, Alessandro
Sathicq, Ángel Gabriel
Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate
topic_facet Química
Amines
Carbamates
Dimethyl carbonate
Green chemistry
N-methylamines
description The mechanism of the reaction between amines with dimethyl carbonate (DMC) has been investigated. Whereas in the absence of bases, they give methylation and carboxymethylation reactions without selectivity (BAl2 and B Ac2 mechanisms, respectively), in the presence of bases, the B Ac2 mechanism prevails. The carbamate already formed reacts further with DMC via the BAl2 mechanism to give the corresponding N-methyl derivative. Such pronounced double selectivity has been explained in terms of Pearson's Hard-Soft Acid-Base (HSAB) theory. Accordingly, N-methylcarbamates have been prepared from primary aliphatic and aromatic amines, either at reflux temperature of DMC (90 °C) or at 230 °C in autoclave. The reaction can be carried out in one step or through the isolation of the carbamate and the subsequent methylation reaction with DMC. This method is the direct synthesis, in high yield and selectivity, of secondary N-methylamines from the corresponding primary amines.
format Articulo
Articulo
author Tundo, Pietro
Bressanello, Salima
Loris, Alessandro
Sathicq, Ángel Gabriel
author_facet Tundo, Pietro
Bressanello, Salima
Loris, Alessandro
Sathicq, Ángel Gabriel
author_sort Tundo, Pietro
title Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate
title_short Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate
title_full Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate
title_fullStr Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate
title_full_unstemmed Direct synthesis of N-methylurethanes from primary amines with dimethyl carbonate
title_sort direct synthesis of n-methylurethanes from primary amines with dimethyl carbonate
publishDate 2005
url http://sedici.unlp.edu.ar/handle/10915/83369
work_keys_str_mv AT tundopietro directsynthesisofnmethylurethanesfromprimaryamineswithdimethylcarbonate
AT bressanellosalima directsynthesisofnmethylurethanesfromprimaryamineswithdimethylcarbonate
AT lorisalessandro directsynthesisofnmethylurethanesfromprimaryamineswithdimethylcarbonate
AT sathicqangelgabriel directsynthesisofnmethylurethanesfromprimaryamineswithdimethylcarbonate
bdutipo_str Repositorios
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