Work

Asymmetric 1,2‐Carbamoyl Rearrangement of Lithiated Chiral Oxazolidine Carbamates and Diastereoselective Synthesis of α‐Hydroxy Amides

Year: 2022

Type: article

Abstract: Asymmetric 1,2-carbamoyl rearrangement of lithiated 2-alkenyl carbamates has been investigated. Deprotonation of chiral 2-alkenyl oxazolidine carbamates with sec-butyllithium in ether at -78 °C followed by warming of the resulting 1-lithio-2-alkenyl derivatives to room temperature resulted in 1,2-carbamoyl rearrangement to provide α-hydroxy amides. The rearrangement proceeded with excellent diastereoselectivity and in good to excellent isolated yield of the α-hydroxy amide derivatives. The substrate scope of the reaction was investigated with a variety of 2-alkenyl and benzyl oxazolidine carbamates. A stereochemical model is provided to explain the stereochemical outcome associated with the rearrangement. Acid-catalyzed removal of the chiral oxazolidine afforded α-hydroxy acid in high optical purity.

Source: Chemistry - A European Journal

DOI: 10.1002/chem.202200941

Authors: Arun K. Ghosh, Amartyo J. Basu, Che‐Sheng Hsu, Monika Yadav

Institution: Purdue University West Lafayette

Language: English

Topic: Coordination Chemistry and Organometallics

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: Foundation for the National Institutes of Health, National Cancer Institute, National Institute of Allergy and Infectious Diseases

Awards: G3221994488, Cancer Center Support Grant, Design & Synthesis of Nonpeptide Protease Inhibitors, Design & Synthesis of Nonpeptide Protease Inhibitors