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Introduction

Jorgensen conducted research across various chemistry disciplines, such as physical chemistry and biochemistry. He focused on applications of computational chemistry to issues that may arise in these fields.

CAMEO Computer-Program Contributions

CAMEO (Computer-Assisted Mechanistic Evaluation of Organic reactions) is a multifaceted computer program developed by the Environmental Protection Agency (EPA) and National Oceanic and Atmospheric Administration (NOAA).  It consists of four programs: CAMEO fm, CAMEO Chemicals, MARPLOT, and ALOHA. CAMEO Chemicals provides physical, hazard, emergency, and reactivity data on chemicals. It can be used to predict products, given starting materials and reaction conditions. Jorgensen, along with Genevieve D. Paderes and Pascal Metivier, contributed to the development of CAMEO, expanding the database to include algorithms to predict oxidation, reduction, and ene and retro-ene reactions. [1] [2] [3]

In developing an algorithm to predict products of oxidation reactions, both Jorgensen and Paderes did not utilize reaction mechanisms, as is the usual method. This is due to limited availability of knowledge on the mechanisms, numerous potential intermediates, and the product dependence on oxidizing agent reactivity and reaction conditions. Instead, they opted to oxidize a set of 21 synthetically useful oxidizing agents under various reaction conditions in order to observe the effects of oxidation on a molecule. Additionally, they noted the structural specifications, like stereochemistry, strain, and substituents of the reagents. By focusing on these aspects of the oxidation reaction, they were able to observe how different oxidizing agents affect the same reagent – perhaps by oxidizing one functional group over another. [1]

Jorgensen, alongside Paderes and Metivier, worked to improve the products of various hydride reduction reactions. Their method required extensive research on individual hydride reducing reagents to ensure the predicted product takes into account the comprehensive reactivities of the reagents. First, they classified each reducing agent as electrophilic or nucleophilic. Subsequently, they ranked the reducing agents in terms of strength in reducing and not reducing certain functional groups. They observed the various mechanisms that the reducing agents can undergo with certain starting materials. They took into account the several alternative pathways a reaction can take. In sum, they accounted for reducing reagent reactivity, chemoselectivity, regioselectivity, and potential alternative pathways. [2]

Research on ene and retro-ene, also known as Diels-Alder reactions, called for frontier molecular orbital (FMO) theory to predict products for pericyclic reactions. FMO theory is used to predict the regioselectivity of the reagents. In addition, an algorithm for prediction of the FMO energies is consistent with literature values. [3]


References

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  1. ^ a b Paderes, G.D., Jorgensen, W.L. J. Org. Chem. 1989. 54. 2058-2085
  2. ^ a b Paderes, G. D., Metevier, P., Jorgensen, W. L. J. Org. Chem. 1991. 56. 4718-4733
  3. ^ a b Paderes, G.D., Jorgensen, W.L. J. Org. Chem. 1992. 57. 1904-1916.