Page 211 - Academic Press Encyclopedia of Physical Science and Technology 3rd Organic Chemistry

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Encyclopedia of Physical Science and Technology en011-542 July 26, 2001 15:33

Organic Chemistry, Synthesis

John Welch
State University of New York, Albany

I. Functional Group Manipulation
II. Carbon Carbon Bond Forming Reactions
III. Natural Product Synthesis
IV. Asymmetric Synthesis
V. Biomimetic Synthesis

GLOSSARY Retrosynthetic analysis Systematic bond disconnec-
tion of a synthetic target for purposes of planning a
Asymmetric synthesis Stereoselective preparation of a synthesis.
single enantiomer.
Biomimetic synthesis Construction of molecules by
mimicking biosynthetic processes. ORGANIC SYNTHESIS, the science of the preparation
Diastereoselectivity Tendency of a reagent or reactant to of organic molecules, is a crucial element of organic chem-
form a single diastereomer in a reaction. istry. It is synthesis that makes possible the preparation
Electrophilicity Tendency of a reactant that is electron of materials with novel structures and facilitates the study
deficient to satisfy this deficiency in a reaction. of naturally occurring substances otherwise available only
Enantioselectivity Tendency of a reagent to form a single after tedious and exacting isolation. The synthetic chemist
enantiomer in a reaction. is often called upon to test the latest advances in theory by
Functional group Structural feature of a larger molecule preparing new molecules; yet the observations of the syn-
which imparts to that molecule a particular chemical thetic chemist frequently contribute to the development of
reactivity. Functional groups often contain heteroatoms new theories.
but may also result from changes in hybridization or Organic chemistry, as the chemistry of carbon com-
bonding. pounds, requires the functionalization of these compounds
Natural products Molecules formed by biological or- to prepare new substances. Once functionalized, construc-
ganisms. Natural products are frequently chiral and of- tion of new carbon molecular frameworks is possible. His-
ten complex. torically, the preparation of natural products has been the
Nucleophilicity Tendency of a reactant that has an elec- most important application of synthetic methods. Con-
tron pair available for bonding to contribute this elec- temporary chemists not only seek to prepare the chiral
tron pair in a reaction. natural compounds efficiently by asymmetric synthesis
Regioselectivity Ability of a reactant to discriminate and but, by utilizing biomimetic strategies, to copy the biosyn-
principally form a single regioisomer. thetic pathways.

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