Learn- More Weblinks . http://www.britannica.com/EBchecked/topic/94652/carbanion . http://www.youtube.com/watch?v=H86ZjDdPR-U . http://www.chem.wisc.edu/areas/reich/chem842/_chem842-01-intro%7B03%7D.htm . http://agrawalravin.blogspot.in/2013/03/carbanion.html . http://www.youtube.com/watch?v=fxXyuGLutgw . http://www.youtube.com/watch?v=l6LYVxx2u3s Suggested Readings . Reactive Intermediates in Organic Chemistry: Structure, Mechanism, and Reactions. By Maya Shankar Singh . Carbanion chemistry: structures and mechanisms. By E. Buncel, Julian Michael Dust . Carbanion chemistry. By Robert Brown Bates, Craig A. Ogle. Advanced Organic Chemistry: Reactions, Mechanisms And Structure, 4th Ed. By Jerry March CHEMISTRY PAPER No.5:Organic Chemistry-II (Reaction Mechanism-1 MODULE No. 7: Generation, structure, stability and reactivity of carbanions. Glossary A Aromaticity: It is a chemical property which provides extra stabilization by utilising the conjugated ring of unsaturated bonds, lone pairs, or empty orbitals. B Base: A base is a substance whose aqueous solution, is slippery, bitter, turns red litmus paper blue, produce hydroxide ions (OH-). C Chiral: A chiral molecule has a non-superposable mirror image and an asymmetric carbon atom. Conjugation: The overlap of one p-orbital with another across an intervening sigma bond. D Decarboxylation: A chemical reaction that removes a carboxyl group and releases carbon dioxide (CO2). D Dithiane: A heterocyclic compound with cyclohexane core structure where two methylene bridges are replaced by sulphur atoms (1,2-dithiane, 1,3-dithiane and 1,4-dithiane). E Electronegative: It is the tendency of an atom or a functional group to attract electrons (or electron density) towards itself. I Inversion: The inversion of a chiral center in a molecule in a chemical reaction. M Metallation: It is a chemical reaction which results in a metal atom being attached to an organic molecule. CHEMISTRY PAPER No.5:Organic Chemistry-II (Reaction Mechanism-1 MODULE No. 7: Generation, structure, stability and reactivity of carbanions. N Nucleophile: A chemical species that an donate electron pair to an electrophile to form a chemical bond. O Organometallic compounds: Organometallic compounds are those which contain chemical bonds between carbon and a metal. U Umpolung: The chemcal modification of a functional group with the reversal of polarity of that group. Y Ylide: A ylide or ylid is a neutral dipolar molecule containing forma negatively charged atom directly attached to a heteroatom with a formal positive charge (nitrogen, phosphorus or sulfur). Did You Know? Description Image The concept of Umpolung (German word for reversed polarity) was introduced by D. Seebach and E.J. Corey. Umpolung is the modification of a functional group to reverse the polarity of that group. Dieter Seebach is a German chemist. He is known for his synthesis of biopolymers and dendrimers, and for his contributions to stereochemistry. He became professor for organic chemistry at the University of Giessen. After six years he was appointed D. Seebach (1937) professor at the ETH Zurich. http://www.ae- info.org/ae/User/Seebach_Dieter Elias James Corey is an American organic chemist. He won the 1990 Nobel Prize in Chemistry for his development of the theory and methodology of organic synthesis. He is regarded as one of the greatest living chemists. E.J. Corey (1928) http://en.wikipedia.org/wiki/Elias_James_Co rey Source: http://en.wikipedia.org/wiki/Umpolung CHEMISTRY PAPER No.5:Organic Chemistry-II (Reaction Mechanism-1 MODULE No. 7: Generation, structure, stability and reactivity of carbanions. Description Image Georg Wittig was a German chemist. He gave a method for synthesis of alkenes from aldehydes and ketones using compounds called phosphonium ylides in the Wittig reaction. He shared the Nobel Prize in Chemistry with Herbert C. Brown in 1979. Georg Wittig (1897–1987) Source: http://en.wikipedia.org/wiki/Georg_Wittig Source: http://en.wikipedia.org/wiki/Georg_Wittig Description Image Erich Armand Arthur Joseph Hückel was a German physicist and physical chemist. He is known for the Debye–Hückel theory, the Hückel method of approximate molecular orbital (MO) calculations on π electron systems and proposing Huckel rule for aromaticity. Erich Armand Arthur Joseph Hückel (1896-1980) Source: http://en.wikipedia.org/wiki/Erich_H%C3%BCckel Description Image Rainer Ludwig Claisen was a German chemist. He is known for ondensations of carbonyls and sigmatropic rearrangements. In 1874 he started his academic career at University of Bonn. CHEMISTRY PAPER No.5:Organic Chemistry-II (Reaction Mechanism-1 MODULE No. 7: Generation, structure, stability and reactivity of carbanions. Rainer Ludwig Claisen (1851– 1930) Source: http://en.wikipedia.org/wiki/Rainer_Ludwig_Claisen CHEMISTRY PAPER No.5:Organic Chemistry-II (Reaction Mechanism-1 MODULE No. 7: Generation, structure, stability and reactivity of carbanions. .