The effective molarity (EM)--a computational approach.

Area of Science:

• Organic Chemistry
• Computational Chemistry
• Reaction Mechanisms

Background:

• Intramolecular S(N)2 reactions are crucial for synthesizing cyclic compounds like aziridines and epoxides.
• Determining effective molarity (EM) experimentally can be challenging for certain intramolecular processes.

Purpose of the Study:

• To compute effective molarity (EM) for 12 intramolecular S(N)2 reactions.
• To establish a correlation between calculated and experimental EM values.
• To explore computational methods for predicting EM in difficult-to-study reactions.

Main Methods:

• Ab initio calculations
• Density Functional Theory (DFT) methods
• Computation of effective molarity (EM)

Main Results:

• A strong correlation was observed between computed and experimentally determined effective molarity (EM) values.
• The study successfully predicted EM for intramolecular reactions.
• Calculations identified proximity orientation and strain energies as key driving forces for ring-closing reactions.

Conclusions:

• Computed effective molarity (EM) can reliably predict experimental values for intramolecular S(N)2 reactions.
• Computational methods offer a viable alternative for determining EM when experimental data is scarce.
• Nucleophile-electrophile proximity and product/reactant strain energies are critical factors in these cyclization reactions.