An- Najah National University Civil Engineering Department. Submitted by: Isra Ziad Algorbia Supervisor :Dr.Fuad Mahmood 4-2011. Appel reaction. Table of Contents . Objectives Background Reaction and Mechanism Application and recent literature Conclusion references. Objectives.
Rolf Appel, the discoverer of the Appel reaction, was an element organic, organophosphorus and phospha-alkene chemist who was a research assistant in Chemistry at Boon University in Bonn, Germany. Appel was born in 1921, and received his PhD at age 30. Appel was appointed in 1962 to both the University of Bonn along with the inorganic chemical institute in 1962 from the University of Heidelberg. Appel developed the Appel reaction and published this work for the first time in December 1975 in the Journal Angewandte Chemie in Volume 14, pages 801-811. In 1986, Appel received the Liebig Medal, a prestigious chemistry award in Germany and - in 1986, the same year that he retired from the inorganic institute. After his retirement, he was succeeded by Edgar Neicke from Bielefeld University. 
The Appel Reaction
The reaction of triphenylphosphine and tetrahalomethanes (CCl4, CBr4) with alcohols is a ready method to convert an alcohol to the corresponding alkyl halide under mild conditions. The yields are normally high.
The initial step of the Appel reaction is the formation of the phosphonium salt pair 2. Deprotonation of the alcohol, forming chloroform3, yields an alkoxide ion pair 4. The nucleophilic displacement of the chloride by the alkoxide yields intermediate 5. With primary and secondary alcohols, the chloride anion reacts in a SN2 process forming the desired alkyl chloride 6 and triphenylphosphine oxide7. Tertiary alcohols form the products 6 and 7 via a SN1 mechanism.
*The Appel reaction is used in the formations of alkyl halides, which are molecules consisting of carbons and at least one halide.
*Some commonly known and used alkyl halides include:
1-Chloroform - Chloroform was previously used as an anesthetic but was later found to cause cancer, especially of the liver and kidneys 
2-Carbon tetrachloride - Carbon tetrachloride is found in some dry cleaningsolvents and fire extinguishers but can cause liver damage 
3-Chlorofluorocarbons - Chlorofluorocarbons have been used in refrigerants like air conditioners, but more recently have been shown to deplete the ozone layer. Chlorofluorocarbons can also be used in propellants, like in aerosolinhalers used to treat asthma. As these demonstrate, alkyl halides can be extremely useful in everyday life but also seem to have many negative side effects. 
ROMPgel-Supported Triphenylphosphine with Potential Application in Parallel SynthesisE. Arstad, A. G. M. Barrett, B. T. Hopkins, J. Koebberling, Org. Lett., 2002, 1975-1977
Conversion of alcohols to bromides using a fluorous phosphineL. Desmaris, N. Percina, L. Cottier, D. Sinou, Tetrahedron Lett., 2003, 44, 7589-7591
The facile preparation of alkenyl metathesis synthonsT. W. Baughman, J. C. Sworen, K. B. Wagener, Tetrahedron, 2004, 60, 10943-10948
Chemoselective Isomerization of Secondary-Type Propargylic Alcohols to Propargylic/Allenic Bromides, and Brominated Dienes with Appel-Type Reaction ConditionsN. Sakai, T. Maruyama, T. Konakahara, Synlett, 2009, 2105-2106
*As a result , we can say that Appel reaction is an important reaction ,so to develop its applications it is important to do more and more researches.
 From Wikipedia, the free encyclopedia
ab Appel, Rolf (1975). "Tertiary Phosphane/Tetrachloromethane, a Versatile Reagent for Chlorination, Dehydration, and P?N Linkage". Angewandte Chemie International Edition in English14 (12): 801–811. doi:10.1002/anie.197508011.
 Organic Chemistry Portal
 Lim, J.-S.; Lee, K.-J. J. Heterocycl. Chem. 2002, 39, 975.
 From Wikipedia, the free encyclopedia
 Nishida, Y.; Shingu, Y.; Dohi, H.; Kobayashi, K. Org. Lett. 2003, 5, 2377
 Cho, H. I.; Lee, S. W.; Lee, K.-J. J. Heterocycl. Chem. 2004, 41, 799.
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