Pyrrolidinyl-camphor derivatives as a new class of organocatalyst for direct asymmetric Michael addition of aldehydes and ketones to beta-nitroalkenes.
Chemistry
; 16(23): 7030-8, 2010 Jun 18.
Article
em En
| MEDLINE
| ID: mdl-20455225
ABSTRACT
Practical and convenient synthetic routes have been developed for the synthesis of a new class of pyrrolidinyl-camphor derivatives (7 a-h). These novel compounds were screened as catalysts for the direct Michael addition of symmetrical alpha,alpha-disubstituted aldehydes to beta-nitroalkenes. When this asymmetric transformation was catalyzed by organocatalyst 7 f, the desired Michael adducts were obtained in high chemical yields, with high to excellent stereoselectivities (up to 982 diastereomeric ratio (d.r.) and 99 % enantiomeric excess (ee)). The scope of the catalytic system was expanded to encompass various aldehydes and ketones as the donor sources. The synthetic application was demonstrated by the synthesis of a tetrasubstituted-cyclohexane derivative from (S)-citronellal, with high stereoselectivity.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Pirrolidinas
/
Cânfora
/
Cicloexanos
/
Monoterpenos
/
Aldeídos
/
Alcenos
/
Cetonas
/
Nitrocompostos
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Taiwan