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Introduction to Organic Chemistry and Biochemistry Instructor Dr. Upali Siriwardane (Ph.D. Ohio State) E-mail: upali@chem.latech.edu Office : 311 Carson Taylor Hall ; Phone: 318-257-4941; Office Hours : MTW 9:00 am - 11:00 am; TR 9:00 - 10:00 am & 1:00-2:00 pm.
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Introduction to Organic Chemistry and Biochemistry Instructor Dr. Upali Siriwardane (Ph.D. Ohio State) E-mail: upali@chem.latech.edu Office: 311 Carson Taylor Hall ; Phone: 318-257-4941; Office Hours: MTW 9:00 am - 11:00 am; TR 9:00 - 10:00 am & 1:00-2:00 pm. Chemistry 121(01) Winter 2012 December 16, Test 1 (Chapters 12-13) January 20 Test 2 (Chapters 14-16) February 6 (Chapters 17-19) February 27, (Chapters 20-22) February 28, 2012, Make Up Exam: Bring Scantron Sheet 882-E
Chapter 15: Aldehyde and Ketones Sections
Chapter 15: Aldehyde and Ketones • 15.1 The Carbonyl Group15.2 Structure of Aldehydes and Ketones15.3 Nomenclature for Aldehydes15.4 Nomenclature for Ketones15.5 Isomerism for Aldehydes and Ketones15.6 Selected Common Aldehydes and Ketones15.7 Physical Properties of Aldehydes and Ketones15.8 Preparation of Aldehydes and Ketones15.9 Oxidation and Reduction of Aldehydes and Ketones15.10 Reaction of Aldehydes and Ketones with Alcohols
Structure • the functional group of an aldehyde is a carbonyl group bonded to a H atom • the functional group of a ketone is a carbonyl group bonded to two carbon atoms
IUPAC Nomenclature of Aldehyde and Ketones • The IUPAC system deals with functional groups two different ways. • Modification of the hydrocarbon name to indicate the presence of a functional group. • aldehyde, -CHO use -al ending. • Ketones -RCOR’ use -one ending.
Example C - C - C - C - CHO • Base contains 5 carbon • - aldehyde name is pentane • - remove -e and add -al C - C - C - C - CO-C-C • Base contains 7 carbon • - aldehyde name is heptane • - remove -e and add -one • 3-heptanone
Name the Aldehyde • 2,4-dimethylpentanal
Common Names • Aldehydes: • Fomaldehyde: HCHO • Acetaldehyde: CH3CHO • Propionaldehyde: CH3CH2CHO • Butyraldehyde: CH3CH2CH2CHO • Valeraldehyde: CH3CH2CH2CH2CHO • Ketones: • Acetone: CH3COCH3 • Methyl ethyl ketone CH3CH2COCH3 • Butyl propyl ketone CH3CH2CH2CH2COCH2CH2CH3
Important Aldehydes • Methanal or formaldehyde • Ethanal or acetaldehyde • 2-Propanone or acetone • 2-Butanone or methyl ethyl ketone • Oil of almonds or benzaldehyde • Oil of Cinnamon or cinnamaldehyde • Oil of vanilla beans or vanillin • Mushroom flavoring or 2-octanone • Oil of lemongrass or citral:
Preapration of Aldehydes: • Partial oxidation of primary alcohols with H2CrO4:
Preapration of ketones: • Oxidation of secondary alcohols with KMnO4, or H2CrO4
Chemical Reactions • Oxidation of aldehyde. • Benedict's Test for aldehydes:
Tollen's Test: • Oxidation of aldehyde. • The commercial manufacture of silver mirrors uses a similar process.
Addition reactions of als & ones • Hemiacetal or hemiketal formation
Aldol Condensation • In biological systems this reaction is catalysed by an enzyme named aldolase.
Keto & Enol tautomers • keto form enol from
Keto & Enol tautomers in sugars aldehyde enol ketone