Scalable Route to Chiral Phosphoramidites

Sergiy G Krasutsky,Sheila H Jacobo

doi:10.5539/ijc.v8n2p64

Abstract

The chiral copper-catalyzed conjugate addition is a well-developed methodology to create asymmetric C-C bonds. Many efforts have been dedicated to design efficient systems and identifying highly efficient ligands. Among the most proficient ligands, the ones possessing a bis-phenol or a bis-naphthol moiety are the most prominent. Herein we describe a scalable convenient route that can afford phosphoramidites in excellent yield.<br />Please find "Figure 1. General structure and application of phosphoramidites" in PDF format.

Highlights

The engagement of chiral phosphoramidites as ligands in enantioselective copper-catalyzed conjugate carbon-carbon bond formation using organozinc reagents has become an essential tool in the hands of a synthetic chemist (Ferringa, 2000)
A series of chiral ligands have been prepared, the preparation of ligand 3 has been described in the literature (Vuagnoux-d’Augustin et al; 2007) and is shown in Scheme 1
The process described within this paper eliminated the silica gel chromatography step and provided a more convenient and efficient approach to chiral phosphoramidites

Summary

Introduction

The engagement of chiral phosphoramidites as ligands in enantioselective copper-catalyzed conjugate carbon-carbon bond formation using organozinc reagents has become an essential tool in the hands of a synthetic chemist (Ferringa, 2000). A series of chiral ligands have been prepared, the preparation of ligand 3 has been described in the literature (Vuagnoux-d’Augustin et al; 2007) and is shown in Scheme 1. This ligand was used in the copper mediated asymmetry-inducing step in a production of taxadienone (Mendoza et al, 2012). The process described within this paper eliminated the silica gel chromatography step and provided a more convenient and efficient approach to chiral phosphoramidites

Results and Discussion

Experimental

Conclusion