(S)-4-Benzyl-2-oxazolidinone

Updated: 2026-08-04

Overview

(S)-4-Benzyl-2-oxazolidinone is a premium chiral auxiliary developed by Professor David Evans in the 1980s. This heterocyclic compound features a stereogenic center at the 4-position, making it invaluable for diastereoselective reactions in complex organic synthesis. The compound's rigid oxazolidinone ring structure enables effective face shielding of substrates during reactions, allowing predictable control over stereochemistry. Its benzyl group provides optimal steric bulk for high selectivity while maintaining reasonable solubility in organic solvents.

Physical and Chemical Properties

This crystalline solid exhibits excellent stability under anhydrous conditions but may degrade upon prolonged exposure to moisture. The oxazolidinone ring demonstrates moderate basicity (pKa ~12) and can form stable enolates with strong bases like LDA or NaHMDS. Key spectroscopic characteristics include distinctive IR absorption at ~1750 cm−1 (C=O stretch) and 1H NMR signals at δ 4.4-4.7 (CH2), 3.5-3.8 (CH), and 7.2-7.4 ppm (aromatic). The compound's optical rotation typically ranges between +45° to +55° (c=1, CHCl3).

Main Applications

Pharmaceutical manufacturers extensively use (S)-BOZ in asymmetric aldol reactions, alkylations, and Diels-Alder transformations. It's particularly valuable for constructing β-hydroxy carbonyl compounds and α-branched carboxylic acid derivatives with >95% ee. In agrochemical production, the auxiliary facilitates synthesis of chiral pesticides and plant growth regulators. Recent research explores its use in polymer-supported catalysis and flow chemistry systems for continuous manufacturing processes.

Safety and Storage

As a mild irritant, proper handling requires nitrile gloves, safety goggles, and fume hood use. Spills should be contained with inert absorbents and disposed as hazardous organic waste. The compound shows no acute toxicity but may cause sensitization upon repeated exposure. For long-term storage, maintain under argon or nitrogen atmosphere at 2-8°C in amber glass containers. Desiccants like molecular sieves (3Å) help prevent hydrolysis. Shelf life typically exceeds 3 years when properly stored.

B2B Procurement Guide

When sourcing (S)-4-Benzyl-2-oxazolidinone, prioritize suppliers with ISO 9001 certification and batch-specific Certificates of Analysis. Technical specifications should confirm ≥99% chemical purity and ≥99.5% enantiomeric excess (HPLC). For pharmaceutical applications, audit suppliers for ICH Q7 compliance and request DMF/ASMF documentation. Bulk shipments (25kg drums) typically offer 15-30% cost savings versus small packaging. Consider just-in-time delivery for moisture-sensitive applications.