We demonstrate a new efficient hybrid MC/MD reaction method with a rare event-driving mechanism as a practical 'atomistic' molecular simulation of large-scale chemically reactive systems. Application of the method to (R)-2-chlorobutane molecules in N,N-dimethylformamide (DMF) molecules starting in the optical pure state (100% e. e.) was found to successfully provide such an atomistic state with similar to 0% e. e., the expected purity of (R)- to (S)-enantiomers of the racemic mixture in chemical equilibrium. This hybrid MC/MD reaction method is promising for studies of various properties in chemically reactive systems and their stereochemistry as well. (C) 2013 Elsevier B. V. All rights reserved.