The Influence of Exocyclic Stereochemistry on the Tethered Aminohydroxylation Reaction

Abstract

A new strategy that employs an exocyclic stereocenter to effect diastereocontrol in the tethered aminohydroxylation (TA) reaction is applied to the stereoselective synthesis of a range of amino alcohols in good to excellent yields, and with anti selectivities of up to 20:1. The influence of the reaction conditions and substrate parameters on the level of diastereocontrol is described. Furthermore, an "inside alkoxy" model is employed to rationalize the sense and degree of stereoselectivity observed in these systems.

Synthetic methods Part (ii) oxidation and reduction methods

“…33 Donohoe has also investigated the influence of exocyclic stereochemistry on the tethered aminohydroxylation reaction. 34 Meanwhile, the group of Luxenburger have prepared ethyl-, benzyl-, tert-butyl and fluorenylmethyl-4-chlorobenzoyloxycarbamates as storable, readily prepared nitrogen sources for the Sharpless aminohydroxylation reaction. 35 …”

Tethered Aminohydroxylation Reaction and Its Application to Total Synthesis

“…More recently, stereocentres located outside of the hetereocycle formed in the reaction have been employed to induce diastereoselectivity in the TA reaction; consider the reaction of the bench stable aroyloxycarbamate precursors 29a-c (Scheme 9). [12] Scheme 9. Employing an exocyclic stereocentre to control the diastereoselectivity during the TA reaction.…”

Diastereoselective Osmium‐catalyzed Vicinal Oxyamination of Acyclic Allylic Alcohol Derivatives

“…Several reports of diastereoselectivity in the intermolecular oxyamination reaction serve to highlight the potential of this element of stereocontrol for the synthesis of amino alcohol containing compounds, 4,13,14 including natural products. Several reports of diastereoselectivity in the intermolecular oxyamination reaction serve to highlight the potential of this element of stereocontrol for the synthesis of amino alcohol containing compounds, 4,13,14 including natural products.…”

“…Several reports of diastereoselectivity in the intermolecular oxyamination reaction serve to highlight the potential of this element of stereocontrol for the synthesis of amino alcohol containing compounds, 4,13,14 including natural products. 14 Herein we disclose a study on the diastereoselectivity of the osmium-catalyzed intermolecular vicinal oxyamination of acyclic allylic alcohol derivatives with benzyl N-(4-tosyloxy)carbamate (1, Scheme 1). Recently, a study reported the influence of exocyclic stereochemistry on the on the intramolecular osmium-catalyzed TA reaction.…”

“…The diastereoselectivity of the osmium-catalyzed oxyamination reaction of chiral alkenes is also of importance for the stereoselective synthesis of amino-alcohol containing products, either in its own right, or as a complicating factor in reactions promoted by chiral ligands. Several reports of diastereoselectivity in the intermolecular oxyamination reaction serve to highlight the potential of this element of stereocontrol for the synthesis of amino alcohol containing compounds, 4,13,14 including natural products. [15][16][17] Despite these disclosures there have been few systematic investigations of the influence of diastereoselectivity in the oxyamination reaction.…”