title: A new tool to guide halofunctionalization reactions: the halenium affinity (HalA) scale.
abstract: We introduce a previously unexplored parameter-halenium affinity (HalA)- as a quantitative descriptor of the bond strengths of various functional groups to halenium ions. The HalA scale ranks potential halenium ion acceptors based on their ability to stabilize a "free halenium ion". Alkenes in particular but other Lewis bases as well, such as amines, amides, carbonyls, and ether oxygen atoms, etc., have been classified on the HalA scale. This indirect approach enables a rapid and straightforward prediction of chemoselectivity for systems involved in halofunctionalization reactions that have multiple nucleophilic sites. The influences of subtle electronic and steric variations, as well as the less predictable anchimeric and stereoelectronic effects, are intrinsically accounted for by HalA computations, providing quantitative assessments beyond simple "chemical intuition". This combined theoretical-experimental approach offers an expeditious means of predicting and identifying unprecedented reactions.
authors.affiliation: Engineering and Process Sciences, The Dow Chemical Company , Midland, Michigan 48674, United States.
authors.forename: Kumar Dilip
authors.initials: KD
authors.lastname: Ashtekar
authors.forename: Nastaran Salehi
authors.initials: NS
authors.lastname: Marzijarani
authors.forename: Arvind
authors.initials: A
authors.lastname: Jaganathan
authors.forename: Daniel
authors.initials: D
authors.lastname: Holmes
authors.forename: James E
authors.initials: JE
authors.lastname: Jackson
authors.forename: Babak
authors.initials: B
authors.lastname: Borhan
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D054879:Halogenation; D006219:Halogens / Q000737:chemistry*; D007202:Indicators and Reagents; D007477:Ions / Q000737:chemistry*; D008958:Models, Molecular; D013816:Thermodynamics
chemical_list: D000475:Alkenes; D006219:Halogens; D007202:Indicators and Reagents; D007477:Ions