Overview

Chemists know 2-chloromandelic acid (typically referenced interchangeably as o-chloromandelic or DL-2-chloromandelic acid) as a multifunctional chiral building block in medicinal chemistry. It’s interesting how that ortho-chloro group and α-hydroxy acid motif work in sync—activating the aromatic ring while enabling versatile stereochemical control. As one lab director put it, this combination makes it a "Swiss Army knife" for pharmaceutical syntheses.

Key Characteristics

       Formula & Weight:C₈H₇ClO₃ | 186.59 g·mol⁻¹
       Physical Form:Fine white to pale cream crystals (naive observers might mistake it for tartaric acid)
       Thermal Behavior:Sharp melting point between 90–93°C; decomposition kicks in around 267°C—meaning it resists distillation but holds up well in reactions
       Density & Handling:1.32 g·cm⁻³ | Store sealed with desiccant; that benzylic hydroxyl means you fight hydration

Frankly, that chlorine atom isn't just along for the ride—it amplifies electrophilicity at the adjacent carbon, while the hydroxyl group opens doors to classic transforms. Think esterifications or stereoselective reductions, even when handling bulk quantities.

Why Industry Relies On It

Pharma’s Chiral Workhorse

Practically every efficiency-driven route to drugs like clopidogrel passes through this intermediate. Its ready-made chirality sidesteps resolution headaches later in synthesis. Scale-up teams particularly favor it—when pilot plants report back, they consistently note purity over 99% after crystallization.

Synthetic Flexibility

Beyond cardiovascular meds, it shines in:
   Controlled nucleophilic substitutions (thank the electron-withdrawing chloro group)
   Pd-catalyzed couplings needing halogen handles
   Asymmetric hydrogenations where its structure guides stereochemistry

CDMOs will tell you busy chem drawers stock this raw material constantly: well-documented behavior, straightforward purification, and grade-for-grade batch consistency make it a production winner.

Storage & Safety Brief

Keep stored cool and dark in sealed containers—moisture ambitious from the start. Wear standard halogen-handling PPE; the MSDS flags skin sensitization potential.

Why It Stays Relevant

Bottom line: 2-Chloromandelic acid delivers where it counts. For process chemists balancing scalability with stereochemical precision, this acid bridges the gap between discovery elegance and manufacturing reality. You’ll find it reliably slotting into routes where cheaper achiral analogs fall short on yield or enantiopurity—especially in anticoagulant and antiplatelet API sequences.