CHEM 13 - Ch. 13 Aldehydes and Ketones The functional group...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Ch. 13 – Aldehydes and Ketones The functional group common to both aldehydes and ketones is the carbonyl group, a C atom with a double bond to a O atom. This group tends to undergoes addition reactions (like what we saw with alkenes with the – C=C- bond), as this group is highly polar. For ketones, two carbon-containing groups (2 alkyl, 2 aryl, or 1 alkyl and 1 aryl) are attached to the carbonyl group, so the general formulas are: R—CO—R’, Ar—CO—R, Ar —CO—Ar’. For aldehydes, one group attached to the carbonyl is instead a H atom, so the general formulas are: H—CHO, R—CHO, Ar—CHO. [When writing condensed structural formulas, one writes aldehydes with –CHO vs –COH to avoid confusion with alcohols. In both –CO- and –CHO, the C to O double bond is implied.] These two families of compounds have some common properties since they share the carbonyl group, but will also show differences in certain types of reactions (e.g., oxidation). Nomenclature for Aldehydes (sect. 13.2) Common names are used for the smaller aldehydes, typically taken from the acids that the aldehydes are oxidized to. Examples are HCHO (formaldehyde) from HCOOH (formic acid), and CH 3 CHO (acetaldehyde) from CH 3 COOH (acetic acid). (Know these two.) The IUPAC names of aldehydes are derived from corresponding alkanes, where the LCC with the –CHO group is chosen, the –e is dropped from the alkane and the ending –al is added. This group takes precedence, so the carbonyl carbon is always Carbon-1 in the numbering of the LCC so it isn’t necessary to be designated. (This is different from alkenes, alkynes, alcohols, where the location of either the double bond, triple bond, or –OH group must be named.) Note the smells of vanilla, almonds, lemongrass, and cinnamon comes from aldehydes (see Fig. 13.3 on p. 425)! Naming Common Ketones (section 13.2)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/09/2008 for the course CHEM 104 taught by Professor Nathan during the Spring '08 term at St. Francis PA.

Page1 / 4

CHEM 13 - Ch. 13 Aldehydes and Ketones The functional group...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online