Overview
Fluorine and Fluorine Derived Products
R&D Manufacturing Facilities

Selective Fluorination

Organofluorine compounds are emerging as chemical specialties of significant and increasing commercial interest. A major driver has been the development of fluorine-containing bio-active molecules for use as medicinal and plant-protection agents. Other new applications involving organofluorine chemistry are in the synthesis of liquid crystals, surface active agents, specialty coatings, reactive dyes, and even olefin polymerization catalysts.

All of these applications require the cost-effective, regiospecific introduction of fluorine or of a fluorine-containing functional group (i.e., CF₃) in an organic molecule. This can often be quite challenging, especially when dealing with a complex organic substrate. Air Products and Chemicals, Inc. (APCI) provides unique reagents, synthetic methodologies, and industrial scale expertise for performing selective fluorination chemistry.

Most fluorine-containing commodity chemicals and some specialties are products of nucleophilic displacement chemistry utilizing hydrogen fluoride or other sources of the fluoride ion. Specific examples are:

• activated KF in halogen exchange reactions for the production of fluoroaromatics
• sulfur tetrafluoride (SF₄), DAST (Et₂NSF₃), and Deoxo-Fluor^TM reagents for the conversion carbon-oxygen to carbon-fluorine bonds (deoxofluorination)

The "deoxofluorination" chemistry specifically converts R₃C-OH to R₃C-F and R₂C=O to R₂CF₂.

Single-step transformation of C-H to C-F linkages and the fluorination of electron-rich centers such as carbanions and aromatics cannot be accomplished with HF chemistry. This type of reaction requires sources of electrophilic F⁺ or radical F^•. Though very reactive, elemental fluorine, when used under highly controlled conditions, can be a source of these fluorinating species. In some cases, performing direct selective fluorination with F₂ is possible. Direct fluorination chemistry is highly substrate dependent, but often in a predictable manner. When direct fluorination is possible, this route can potentially have the lowest cost for introducing electrophilic fluorine.

An alternative, especially for high-value substrates, is the use of electrophilic fluorinating compounds like the Selectfluor® reagent. By functioning essentially as a convenient stoichiometric source of F⁺, the Selectfluor® reagent can fluorinate electron-rich substrates such as aromatics and steroid enolates, often with remarkable regioselectivity. An extensive review of its applications in organic synthesis is included in this folder.

The fluorination of certain organics with F^• radicals can be accomplished with diluted fluorine or high-valent metal fluorides, such as CoF₃. This process usually yields polyfluorinated products, for instance napthalene to perfluorodecalin. However, in some cases, a more limited regioselective fluorinaton may be realized.

Air Products Fluorine Derived Products

• Inorganic Fluorides
  NF₃, SF₆, SF₄, WF₆, ReF₆, BrF₃, CIF₃, IF₅, SiF₄
  
  Markets
  Electronics, Electrical, Metal-working
  
  
• Fluoro Organics
  CF₄, C₂F₆
  Selectfluor®
  Deoxo-Fluor^TM
  Fluoro intermediates
  Surface fluorination of plastics
  
  Markets
  Electrical, Electronics, Pharmaceutical, Agrochemical, Liquid Crystal, Automotive

Air Products Selective Fluorination R&D and Manufacturing Facilities

Corporate Science and Technology Center
Allentown, Pennsylvania, USA

• Discovery, small scale laboratory synthesis
• Well-recognized scientists and engineers in fluorination
• Excellent analytical capabilities

Fluorine Technology Center
Allentown, Pennsylvania, USA

• Process research, development, engineering
• Production of kilogram quantities of fluoro organics
• Technology transfer to pilot plant

Hometown Production Facility
Tamaqua, Pennsylvania, USA

• World-class fluorination production facility
• Pilot plant facility