William Lipscomb’s Contributions to Chemistry

Abstract

William Lipscomb is an American inorganic chemist who was awarded the Noble Prize in chemistry in 1976 for his outstanding contributions to the study of the bonding and structure of the boranes compounds. Boranes are compounds of Boron and Hydrogen which are also called electron deficient compounds because Boron has three electrons, but four orbital. Boranes are finding increasing use in chemistry as well as industry as reagents which can be used in the preparation of other compounds. Boranes compounds have found to be useful in NMR and promising as fuels for high speed jets. William Lipscomb’s work led to a better understanding of bonding at the atomic level and he also used the same techniques to study carboranes, which are compounds consisting of Boron and Carbon atoms. This very brief essay presents the significance of William N. Lipscomb’s contribution to chemistry.

William Nunn Lipscomb is an American chemist who has worked in the fields of experimental and theoretical chemistry as well as biochemistry. He studied at the University of Kentucky and later at the California Institute of Technology. He is an academic and taught at the University of Minnesota as well as Harvard University. He was awarded the Noble Prize in chemistry in 1976 for his work on the molecular structures of boranes using X-ray crystallography (Malmström). A borane is an inorganic chemical compound of Boron and Hydrogen, such as B2H6 or diborane and B4H10 or tetraborane. The lighter boranes are highly unstable and diborane ignites in air to burn with a green flame. The two major classes of boranes are the nidoboranes, which have a general formula BnHn+4 and the arachnoboranes, with a general formula BnHn+6. The salts of boranes are called borohydrides. Because boranes are often unstable compounds, therefore studying them must have been particularly difficult, but being able to deduce the molecular structure of such compounds meant that it was possible to understand the nature of chemical bonds in compounds. The chemistry of the boranes compounds is characterized by boron possessing only three valance electrons, but four valance orbital (Casanova). A chemical bond makes it possible for atoms to be held together in crystals or molecules. As a result of Lipscomb’s work, it was also possible to better understand the relationship of geometric and electronic structures in theoretical, inorganic and organic chemistry, along with the structure as well as the reactivity of electron deficient compounds (Lipscomb). The understanding of the chemical bond has led to the creation of one of the most versatile reagents of modern synthetic chemistry, B2H6 or diborone. The work of William Lipscomb also made it possible for chemists to understand hydroboration, which as a reaction is important because this reaction makes it possible to introduce a large number of functional groups through the use of boranes. The understanding of the nature of chemical bonds made it possible to use mathematical modeling and computational techniques to model molecules, a process which greatly assists in the computational design of drugs. The work of William N. Lipscomb also made it possible for scientists to better understand the bonding and structure of carboranes, and carbocations (Lipscomb).

Borane, carborane and carbocation compounds are electron – deficient compounds. Electron – deficient compounds find applications in leading edge technology areas such as Nuclear Magnetic Resonance or NMR systems which make use of high field values to make their operation possible. The practical applications of the boranes and the carborane compounds are increasing at a significant pace. Because of the work of William N. Lipscomb, who made it possible for scientists to understand the bond structure in simpler boranes compounds, it is now possible to use powerful computational methods to study the structures and bonding in the more complex boranes compounds. A study of diborane is also important because the compound is widely used as a dopent in the semiconductor industry (Wikipedia). Borane based reagents are also used in organic synthesis, such as the conversion of aldehydes and ketones to alcohols. Boranes were at one stage widely researched because of their potential application as high speed fuels for very high speed aircraft. Carboranes are compounds which are composed of clusters of boron and carbon atoms. C2B10H12 or the icosahedral closo-carboranes is a compound which has been used for heat resistant polymers and medical applications, while H(CHB11Cl11) is the carborane super acid which is a million times stronger then sulfuric acid and the only acid which is able to protonate C60 or fullerene without its decomposition. Hence, the work of William N. Lipscomb has opened up new avenues in the understanding of chemistry, chemical bonds, chemical structures and the design of boranes as well as carboranes, which are finding increasing practical uses. The theoretical techniques developed by William N. Lipscomb are also useful in the study of many other compounds (Casanova). 

References / Bibliography

  1.  Casanova, Joseph. “The Borane, Carborane, Carbocation Continuum”. Wiley – Interscience. April 15, 1998. September 19, 2005. http://www.amazon.com/exec/obidos/tg/detail/-/0471180750/002-3884690-5141630?v=glance
  2. Denk, Michael K. “Advanced Main Group Chemistry”. University of Guelph. 2000. September 18, 2005. http://131.104.156.23/Lectures/CHEM_462/462_chapter_1.html
  3. Lipscomb, William N. “The Boranes and their Relatives”. Harvard University. 1976. September 18, 2005. http://nobelprize.org/chemistry/laureates/1976/lipscomb-lecture.pdf
  4.   Malmström, Bo G. and Bertil Andersson. “The Nobel Prize in Chemistry: The Development of Modern Chemistry”. Nobleprize.org. June 28, 2005. September 18, 2005. http://nobelprize.org/chemistry/articles/malmstrom/
  5. Wikipedia, the Free Encyclopedia. “William Lipscomb”. Wikipedia, the Free Encyclopedia. 2005. September 18, 2005. http://en.wikipedia.org/wiki/William_Lipscomb
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