Comparative Nucleophilic Susceptibility of Selected Phosphoro- and Phosphonothiolates by Semi-Empirical Molecular Orbital Calculations
Abstract
The electronic properties of several phosphorothiolates were compared against the target molecule O-ethyl-S-(2-diisopropylaminoethyl)- methylphosphonothiolate (VX) by hierarchical clustering techniques and electrostatic potential maps to determine the best match for nucleophilic attack. Semi-empirical calculations and geometry optimization were accomplished with the MNDO algorithm in MOPAC v5.0. Graphical display of structures and electrostatic potentials were produced, using the Chemo-metric and Biometric Modeling (CBM) Branch's Molecular Modeling, Analysis and Display System (MMADS). The pattern recognition program ARTHUR was used to predict the hierarchical clustering of the electronic properties using Euclidean distance criteria. Both hierarchical clustering and electrostatic potential differences contouring predict that the molecule O-ethyl S-ethyl methylphosphonothiolate most closely resembles VX in susceptibility to nucleophilic displacement. (JS)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1990
- Accession Number
- ADA229664
Entities
People
- George R. Famini
- Philip W. Bartram
Organizations
- Edgewood Chemical Biological Center