Practical Preparation of Chiral 4-Substituted 2-Oxazolidinones

Abstract

A versatile and practical route to both enantiomers of a wide variety of 4-substituted 2-oxazolidinones from the parent heterocycle is provided by regioselective substitutions via 4-methoxy derivative followed by chromatographic separation of the diastereomers derived from N-2-exo-methoxy-1-apocamphanecarbonylation.

Treatment of N-Boc Derivatives of β-Amino Alcohols with N,N-Diethylaminosulfur Trifluoride Leads to Chiral Oxazolidinones: An Unexpected Intramolecular Cyclization

“…Compounds 8, 10 and 14 were characterized with the known samples. Compound 6 and 12 were identified with those described in the literature (6 9 , 12 10 ). c Isolated yields.…”

“…Compounds 8, 10 and 14 were characterized with the known samples. Compound 6 and 12 were identified with those described in the literature (6 9 , 12 10 The general experimental procedure is as follows; DAST (0.66 mL, 5 mmol) was added dropwise to a solution of NBoc derivatives of the b-amino alcohol (5 mmol) in anhydrous dichloromethane (25 mL) at 0 ∞C under nitrogen. The mixture was then stirred at room temperature for 3 h. The reaction was quenched by addition of 10% sodium bicarbonate solution, and the product was extracted with dichloromethane.…”

1,2-Amino Alcohols and Their Heterocyclic Derivatives as Chiral Auxiliaries in Asymmetric Synthesis

“…A versatile and efficient approach to both R-and S-enantiomers of oxazolidinones has been reported and uses a preformed ring as a building block (Scheme 76). 386 All of the products were formed by substitution at the 4-position, followed by chromatographic separation. Valuable access to alkenyl-and alkynyl-substituted derivatives can be realized.…”

A New Preparation of Optically Active N-Acyloxazolidinones via Ruthenium-Catalyzed Enantioselective Hydrogenation

“…N -Acyloxazolidinones are commonly prepared by deprotonation of the parent oxazolidinones in the presence of BuLi 1a,3b,8a or Et 3 N followed by acylation with anhydrides or acid chlorides. Furthermore, acylation with an optically pure acyl chloride has been used to resolve 4-methyloxazolidinone . By using a catalytic amount of PTSA instead of a base, the α-methylene- N -acyloxazolidinones 6 − 9 could be prepared in three steps from tertiary propargylic alcohol, CO 2 , ammonia, and an acyl chloride.…”