Complex Organic Structures

STEM Fair Practice

Chemistry GT 1/26/15

Drill

New seats! Set up your STEM Fair board and

locate your grading sheets (or the ones that were given to you)

Draw the condensed structural formula for pentane.

Objectives

IWBAT• Draw and name alkanes, alkenes, and

alkynes.• Name branched-chain alkanes• Practice presenting my STEM fair board,

and become more comfortable with the presentation portion of the STEM fair.

Practice Presentation

You will be paired up for the purposes of presentation.

One person will present their STEM fair board and the second will ask questions about the experiment (5-7 minutes).

Using the judges’ scoring guide, the second will evaluate the board. (2-3 minutes)

Partners (Set 2)Cook, Michael A Tu, Kara GJacobson, Samuel Washington, OrchidKnudson, Zachary I McKay, Audrey MWhitaker, Samuel R Menjivar Perez, Samuel ADemers, Cory Schluederberg, Katie TOrzechowski, Ella R Thames, Maya WLumsden, Patrick Kanja, GraceAhmed, Tineer Nelson, Victoria MFeinleib, Leanna M Garcia, Immanuel VHouser, Ashley K Sullivan, Paige MWalter, Rachel E Sweet, Sarah ECarey, Jenna L Hilterbrick, Trevor AChau, Nhu T Brown, Lindsey

Let’s Discuss

What was useful? What do you need to improve? What are you going to do to prepare for

the STEM fair?

Alkenes and Alkynes

Alkenes contain a double bond between adjacent carbon atoms.

Alkenes have the general formula CnH2n.

Alkynes contain a triple bond.

Alkynes have the general formula CnH2n-2.

Copyright © 2007 by Pearson Education, Inc. Publishing as Benjamin Cummings

Learning Check

Draw a condensed structural formula for:• butene• pentyne• What do we see is

confusing??

• Maybe we need another way to name.

Identify this structure:

ComplexOrganic

Nomenclature

What do you notice about these molecules?

How about these molecules?

So how can we name molecules so we know the locations of the side chains and the double/triple bonds?

Naming Rules

1. Count the longest chain of consecutive carbons.

2. Use the appropriate prefix and suffix to name the longest chain (same as before)

3. Number the carbons so the double/triple bonds or side groups have the lowest number

Example:

Naming Rules Continued

4. Write the number of the carbon the double or triple bond begins on in front of the name

Example:

You Try!

Naming Rules Continued

5. If there is a side chain:- follow the same naming rules-then name the side chain by writing the number of the carbon it is located on- count the number of carbons in the side chain- use the appropriate prefix for the side chains and add the ending -yl

Example:

You Try!

Naming Rules Continued

6. If there is more than one side chain, the side group names must be written in alphabetical order

Example:

You Try!

Naming Rules Continued

7. If there are multiples of the same side group, it needs to be denoted using a prefix- See example

Example:

You Try!