2 Theoretical Organic Chemistry

Theoretical organic chemistry encompasses a wide range of topics, spanning from high level electronic structural calculations of simple organic molecules using well-established ab initio molecular orbital or density functional theory techniques to computer simulations of chemical reactions and interactions in solution. This article is divided into two sections: theoretical developments and applications. In the former, theoretical advances in linear scaling electronic structure methods for large systems are briefly addressed. The focus, however, is on the development of solvation models and simulation techniques, particularly those using hybrid quantum and classical methods. In the latter section, topics covered in this review include transition structure modeling, aromaticity, conformational and tautomeric equilibria, host—guest modeling, pericyclic reactions and photochemical processes.