Bisphenylene homologues of BINOL-based phosphoramidites: synthesis, stereostructure, and application in catalysis
摘要:
Bis-ortho- and bis-meta-phenylene homologues of BINOL-based N,N-dimethylphosphoramidites were prepared from the corresponding diols by treatment with hexamethyltriaminophosphane. Phosphoramidites derived from bulkier secondary amines were synthesized by 5-phenyl-1H-tetrazole-promoted amine exchange. All the phosphoramidites were obtained as single diastereomers. Their configurations at the C(naphthyl)-C(phenyl) axes were determined by vibrational circular dichroism (VCD) spectroscopy. Preliminary testing of the ligands in copper-catalyzed conjugate addition of diethylzinc to acyclic enones and nitrostyrene gave the corresponding products in up to 74% ee. (C) 2010 Elsevier Ltd. All rights reserved.
Bisphenylene homologues of BINOL-based phosphoramidites: synthesis, stereostructure, and application in catalysis
摘要:
Bis-ortho- and bis-meta-phenylene homologues of BINOL-based N,N-dimethylphosphoramidites were prepared from the corresponding diols by treatment with hexamethyltriaminophosphane. Phosphoramidites derived from bulkier secondary amines were synthesized by 5-phenyl-1H-tetrazole-promoted amine exchange. All the phosphoramidites were obtained as single diastereomers. Their configurations at the C(naphthyl)-C(phenyl) axes were determined by vibrational circular dichroism (VCD) spectroscopy. Preliminary testing of the ligands in copper-catalyzed conjugate addition of diethylzinc to acyclic enones and nitrostyrene gave the corresponding products in up to 74% ee. (C) 2010 Elsevier Ltd. All rights reserved.
Bisphenylene homologues of BINOL-based phosphoramidites: synthesis, stereostructure, and application in catalysis
摘要:
Bis-ortho- and bis-meta-phenylene homologues of BINOL-based N,N-dimethylphosphoramidites were prepared from the corresponding diols by treatment with hexamethyltriaminophosphane. Phosphoramidites derived from bulkier secondary amines were synthesized by 5-phenyl-1H-tetrazole-promoted amine exchange. All the phosphoramidites were obtained as single diastereomers. Their configurations at the C(naphthyl)-C(phenyl) axes were determined by vibrational circular dichroism (VCD) spectroscopy. Preliminary testing of the ligands in copper-catalyzed conjugate addition of diethylzinc to acyclic enones and nitrostyrene gave the corresponding products in up to 74% ee. (C) 2010 Elsevier Ltd. All rights reserved.
Bis-ortho- and bis-meta-phenylene homologues of BINOL-based N,N-dimethylphosphoramidites were prepared from the corresponding diols by treatment with hexamethyltriaminophosphane. Phosphoramidites derived from bulkier secondary amines were synthesized by 5-phenyl-1H-tetrazole-promoted amine exchange. All the phosphoramidites were obtained as single diastereomers. Their configurations at the C(naphthyl)-C(phenyl) axes were determined by vibrational circular dichroism (VCD) spectroscopy. Preliminary testing of the ligands in copper-catalyzed conjugate addition of diethylzinc to acyclic enones and nitrostyrene gave the corresponding products in up to 74% ee. (C) 2010 Elsevier Ltd. All rights reserved.