Stereodivergent Synthesis of Two Novel α-Aminophosphonic Acids Characterised by a cis-Fused Octahydroindole System

• Published in: European Journal of Organic Chemistry 2011-06, Vol.2011 (16), p.3074-3081
• Main Authors: Arizpe, Alicia, Sayago, Francisco J., Jiménez, Ana I., Ordóñez, Mario, Cativiela, Carlos
• Format: Article
• Language: English
• Subjects: Amino acids; Aminophosphonic acids; Chemistry; Diastereoselectivity; Exact sciences and technology; Fused-ring systems; Heterocyclic compounds; Heterocyclic compounds with only one n hetero atom and condensed derivatives; Organic chemistry; Organometalloidal and organometallic compounds; P derivatives; Phosphoproline analogues; Preparations and properties
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.201100229

The synthesis of two new α‐aminophosphonic acids, namely (2S*,3aS*,7aS*)‐ and (2R*,3aS*,7aS*)‐octahydroindole‐2‐phosphonic acids, is described. They are analogues of phosphoproline with a cyclohexane ring fused to the pyrrolidine moiety. The ring junction has cis stereochemistry in both cases, but the two compounds differ in the relative orientation of the cyclohexane and phosphonate moieties. The two amino acids were prepared from a common starting material following stereodivergent routes that provide the desired stereoisomer with complete stereocontrol. The relative configurations of the compounds synthesised were confirmed by X‐ray diffraction analysis. Two analogues of phosphoproline with a cyclohexane ring fused to the pyrrolidine moiety have been synthesised. They differ in the stereochemistry at the α‐carbon atom and have been prepared, with complete stereocontrol, following stereodivergent routes from a common precursor.